Alright so i get that people are angry over the whole "cant bring all Pokemon over" thing but the reasoning behind it doesn't really make sense and i thought i would make a list stating my arguments (and if this has been done before sorry :x).
Before we start there's one big thing that should be first referenced. Gamefreak has always been about the "Gotta catch them all" and stuff in pokemon. Pokemon is after a JRPG and mons are something to collect and train. Now, while the game does have a lot of flexibility room for people not caring to complete the pokedex, wanting to do more competitive, side stuff, etc. it does still have a strong emphasis on being able to collect mons and fill the dex (The story, trading, new random encounters, post-game stuff).
So that already had some form of abrupt change when you say that Pokemon not in the dex won't be able to be sent over. Now, let's go over each point one by one.
1. This is no longer 3DS quality game its much higher resolution thus higher quality models and more time spent recreating said models
And that should sacrifice making mons why exactly? This actually is a decent highlight on an issue a lot of people have with pokemon games direction. Being with a lot of the new hardware a lot of the scaling and art direction takes a bit of a nose dive. You can see this in XY with the rather smaller looking region and stuff as well as fewer mons added and even in SM with the ration of your character to the world being rather...small despite it supposed to be Hawaii.
Now, this isn't a problem inherently, but it is perfectly understandable some would be bothered by such a change. Let alone factoring that their reasoning was they wanted the mons to be more expressive, but so far from what we've seen the only real "added" expression is better textures and the battle gimmick of the game. Now, I won't say they don't have this or the mons being way more expressive, but that would simply be information GF hasn't given us yet and therefore it is understandable why people would consider the contrary.
There is another reason I want to bring but it relates to your second point.
2. The game releases have coincided with the television series as far back as i can remember (granted my memory isn't very good but still). Since theres going to be a new series beginning at the end of this year it only makes sense that they're going to come out with a new Pokemon game representing the new region (please tell me theres Pokemon fans that actually know this).
Firstly, it hasn't been announced yet, secondly that doesn't mean it's a good thing. You see, would you rather have a game that would have the time taken to make it better and rather full of the content fans would expect from the series or would you want to release it the same day as the anime and have to put out this little tid bit of info. I think it's obvious how big this little thing is to the fandom by how SWSH has gone down in popularity due to this (presumably that is).
Now, the anime is more or less its own thing/adaption of stuff from the game so releasing it before the game would be problematic; I would agree, however, I doubt the better course of action would be to release the game when it would normally come out as opposed to taking the time to make the stuff. It's as you said, "not the 3DS" they clearly need more time to make it all and a yearly release might not cut it anymore. But Nintendo frankly isn't going to really let that fly and GF is showing signs of needing more staff if they're going to keep it to a yearly release.
3. bringing over Pokemon for attachment reasons? Alright this i don't understand are there really people out there that would bring a Pokemon over for this reason?
Hey remember when you said you saw flaws with the "reasoning" and how it didn't add up? Well, how is not understanding why someone would want to bring over mons they like for attachment reasons "flawed reasoning". It's a subjective thing some do others don't. Just like the news of the transfer issue with SWSH being important to some while not as important to others.
Also there could be many reasons. "EV training, breeding, stuff for early trade, using your team in some competative, testing stuff, mons you want to do the adventure with" there could be several reasons other than simply "attachment"
I'm sorry if i don't seem as sympathetic to this whole thing as others but as someone who has played since gen one I've just played the games for the joy and fun thats about it.
I applaud you for playing the game the way you want to, so what's wrong with how others want to play it? Again, I think your substituting the whole "why did they choose this?" as it being an emotional outcry when there is issues with the reasons they've levied. Some people have even dissected them better than me, not to mention GF has contradicted itself more than once.
It just seems like all this hubbub is for nothing really (i mean theres Pokemon home for crying out loud just keep em there).
Even if it's over nothing to yah, you did mention you "Don't understand" why it is like this. Have you looked at articles or discussions on this topic? Have you listened to the arguments and points brought up from the faction that wants all the mons in the game? The way you've said this comes off as simply noticing the drama and commenting on it rather than delving into both sides of the argument.
And it's fine we all make mistakes, but I think you misrepresent the people you talk about with the points you've given here.
If theres a key point I'm missing thats fine tell me please! But as it stands i don't really understand why people are so upset about this.
Well, I hope these points help clear some of it up, but I'd encourage you to also look into other articles or discusion stuff that can talk about it better than I.