Take it from someone who peeked in challenger as Yasuo adc this and last year (Sadly I wasnt chall at the end of season But OP.GG date by months proves this year and i can prove last year with image if requested)
I was mostly a Mid main favorites being Le blanc, Katarina and some control mages
**My secondary was Yasuo ADC **
I managed to get challenger twice with yasuo ADC. And I have been playing it consistently for 2 years getting lot of shit from others AND VIOLA LOOK NOW LOOK AT THIS
Yasuo gets insanely hit with IE changes (overlaps with ultimate, price increase, you should actually avoid this item on yasuo nowdays its no longer a core) , His Rush PD also got its cost increased
AD carries get hit simultaneously losing like 4 AD early game on average as well as some health regen.
Yet yasuo is now meta? NO YASUO ADC WAS META SINCE HIS FKING RELEASE (His realeas was in december 2013) but he was in incognite mode
I started playing yasuo when lifesteal quints gave 4.5% lifesteal.... Back at his release they even gave 6% he was even better back then
The lifesteal got compensated with fleet/taste of blood somewhat well
Bassicly what I am saying is. You are not advanced if you are playing meta you are advanced if you are playing something which destroys meta
Yasuo is most successful non ADC in botlane
Swain is imo second most successful non ADC (getting nerfed for a reason)
Vladimir is up there his coldowns early game are so high any 2vs2 all in could end him but then again does vlad really fall off easy
Xerath is bad... straigh up
Ziggs is most overated one, good luck hiting anyone in decent elo no matter how good you aim because high elo doges way to good
Mordekaiser is succesful but niche requires Pyke/thresh/blitz perhaps zilean and nautilus (granted naut is in bad state)
Want a counter for yasuo? Xayah, Jhin
Want a counter for swain=? Bruisers
You might be facing players who are ahead of meta and are therefore creating new meta. But realisticly you are getting players who are running conqueror on yasuo ADC maxing Q, and having no idea what the fk they are doing since this is something fresh. Its ok not to know thats how you learn
Boards overhyped non AD carries are a bit
Apart from Yasuo, Swain, Vlad, irelia before nerfs, and Perhaps donger everything else is no more niche then it was before.