The roles are unevenly spread. There are some women in some roles who are good enough to play academy.
But people like you want to pigeonhole it in a disingenuous way.
If a team of 5 women can't compete, then all women players must suck.
Mate that's not how league works. If you are a great ADC, but your top and mid are not of a required level you're not going to look great.
Giyuu (Lebanon) is a great player. I know for a fact if he wanted to go LEC he could have. But force him to play his entire career with other Lebanese players against LFL teams and he's going to look bad. The people will just assume "all Lebanese players are bad, look how badly he did when they played vs real pro teams".
Also by denying players access to academy we are denying ANYONE the chance to make a breakthrough. There are many players (including women, but of all genders) who would be close to or at LCS level if they got to play with CoreJJ for a year (maybe not as good as Yeon, but good enough to play LCS). But they will never get the chance.
I've scouted a ton of players over the years, some of them I've later found out were women (maybe more were I just have no idea). 3 (maybe 4) of them would have been great to have at academy level, a further 5-7 would have been worth a tryout at least. One of them I was CERTAIN would be LCS level one day, I even told a Riot employee working on LCS to keep an eye out on them for future years.
Of those, 2 were ADC, one was mid, one was top (ironically no supports which is the meme). Again want to stress that this is only my experience and only who I know, I'm sure there are plenty of good players who play other roles I just didn't know about (e.g. Mayumi in Brazil).
Of those, all 4 one still plays occasionally, but goes to school, the other 3 retired without ever getting a shot (one plays Valorant I think).
And those are just the ones that I found. Who knows how many I missed.