Lots of wargamers (especially the historical/moderns crowd) want simple rules that they don't have to really think about, so they can basically just turn up, push some models around and roll some dice (usually in big multiplayer games, I've noticed).
BattleTech... Is not really that sort of game; never really has been. (Nor are the other games I play*, one of which I wrote myself, and and arguably even more niche than BattleTech; both are tactically demanding and the most of the pair (Maneouvre Group) is ostensibly the least crunchy of the two, but is basically a real-world tactics simulator that is, like, the equivalent of playing a Paradox Grand Strategy on ironman in hard mode.
(It is with supreme irnoy that I note this, since I prefer my COMPUTER games to be on easy mode, while my tabletop games to be challenging, which is apparently the diametic opposite of almost the entire population of the planet (which is par for the course).)
My attitude to well, anything, is that if it's not worth a huge amount of my time, it's not worth any of my time. Which is why the most "casual" of games I play - BattleTech, which I play specifically so I don't have to write scenarios and play exclusively pick-up games... Only has 310 mechs attached to it** and the house rules only runs to 21 pages. (Of which the majority is pretty much mostly a combined weapons/equipment table, since I was fed-up of looking through several different books even AFTER the BattleMech Manual.)
Not every set of rules has to or ever SHOULD try to appeal to everyone, since many people have diametrically opposite viewpoints on what they want out of a game.
*Actually, nor are my RPGs that I run; D&D 3.5 and Pathfinder weren't crunchy ENOUGH for me, so I spent 1500+ pages of houserules combining them, and my second system of choice is ROLEMASTER.
**Granted, that number was double what I started 2020 with because lockdown.