Relatively new player here. I actually agree. I started at the very end of legion. I leveled to 20, it was pretty terrible, but the artwork and music kinda got me. I bought a boost, so started at max level, and was able to kinda meander my way into mythic+. The rest is history.
I do think they need to dramatically lower the time it takes to level in new expansions. 2hours straight, max.