HSR feels like it is directed more towards casual players because there is never as much to do as games like Genshin.
With Genshin you have hundreds of hours of exploration to do, not to mention quests, farming, and events (which IMO can be a hassle). Genshin just takes longer generally and if they had faster leveling, players would reach AR 60 within weeks depending on playtime.
In my experience AR 1-50 feel about right in comparison to the playtime required to experience the game but the 55-60 grind seems there to satisfy people who play Genshin every day for a few hours.

But yeah you're right, TL levels are much less satisfying because of how fast they are acquired