This is an interesting question, because Scarlet and Violet, at times, are as difficult as you want them to be. Want to steamroll the game with the same 6 overleveled Pokémon and beat the challenges in the "correct" order? Go ahead. Wanna screw around with team compositions, the now always-accessible boxes, and exploration? You've just made the game a bit more challenging.
I found Scarlet and Violet to be a little hard, mainly because of the way I structured my teams. A Mono-Poison team had Tulip, Rika, and Poppy to worry about, not to mention Larry beating me because I was underleveled, as well as Nemona (I'm embarrassed to admit I lost to Geeta too); Arven provided a difficult fight for my team full of single-stagers and an indecisive team composition (which I didn't, for some reason, add my Falinks to); and my more conventional team for Starfall Street made it out just fine (although Mela was a nightmare since I fought her first, and Clavell proved a strong foe). I lost to the final boss and Arven in the first Academy Ace Tournament once as well.
Overall I have a feeling me intentionally handicapping my teams and thinking held items will solve everything has something to do with how difficult I think SV is. In actuality the games would probably be a lot easier if I actually played like a kid, but that's really not how I want to play. I really liked preparing a mono-Rock team specifically in preparation for the Brassius and Kofu rematches and giving each member of the team a moment to shine, and I'm a fan of using off-beat, sometimes suboptimal picks such as Oricorio and Tropius; inherent disadvantages like those that I placed upon myself made my playthrough all the more fun and satisfying.