Stop it

Honestly that situation is a failure of communication across all players involved. People who queue for Bot are not necessarily practiced at mages or fighters, some of them are long time Marksmen mains. Communication is key here, and just because there's a flashy new thing down bot lane doesn't mean it can be expected of people just yet.

If you're playing a Marksman in another role pay attention to your team and their preferred picks, otherwise you could end up handicapping someone.

Well when you look at it the right way yeah basically marksmen have swapped with mages, since midlane is easier to power farm marksmen are strongest there. As bot lane is more kill/gold +support pick, mages are stronger there, now you ether deal with it or you settle it.

I do just fine with Jhin bot, depending on the day. I really don't understand the whole "marksmen are trash pick another class" meta.

I will play Miss Fortune because she's my best champion. I am not going to try to force someone else to play something specific (beyond "front line because we have 3 ranged champs picked and it's you and me still left to pick")