That's true, but Konami likes to add a bit of support to random archetypes when they're no longer relevant. Hence, we have Smartfon, haha. So maybe in a couple years from now, we'll see a random Morphtronic Synchro pop out of nowhere. (Then again, the 5D's manga hasn't ended yet, so there's always still a chance, even if it's a slight one.)
Haha, thanks!
Yep, though they also have plenty of ways to make Xyz monsters. Like, if you destroy a monster using 919 "Kuick," you can revive another level 4 Karakuri and go for that Rank 4 Xyz. Or, you can use the extra normal summon from 224 "Ninishi" to bring out another level 3, and then you can make a Rank 3 Xyz. Heck, you can really mess with your opponent because they wouldn't know if you wanted to bring out a Synchro or an Xyz, so you catch them off guard. :P