No problem friend. It is fairly hard to handle all those other phones - see how LineageOS keeps it’s supported list fairly small!

Apple routinely slows down its phones with every major update, promoting people buying $1k+ phones every 2-3 years.

Pixels are the main target of aftermarket ROMs because they are reference Android devices with highly available unlocked developer modes. Most companies producing phones do things like add propriety changes that require substantial workarounds for relatively basic hardware functionality and make it much more difficult to even install an aftermarket ROM.

Really this is all a consequence of capitalism itself and the need to lock in ecosystems to establish controlled markets (allowing for controlling one’s own profit). Every phone could be fully unlockable and hackable by the end user, but companies specifically prevent this in order to maximize their own profits.