Hey, this is is a very interesting question! OK, before I give my own opinion, what does it mean "all the guys who come into football"? If I take that as "all the guys that play football" then 1% seems WAY too high!
OK so my opinion is that obviously it has to be a low percentage - you will never be able to make that a really high percentage - because there are only so many pro places to fill, even if you removed all foreigners and even if some young players were to try to break through abroad, which very few do for some reason. So I think it is normal that the percentage is low. However, that does not mean that the overall quality shouldn't be higher.
I also think that football academies should be organised completely differently, but that is probably too much to go into now.
I have a related question: it seems that here, quite a few people think that if a player hasn't broken through at 21, they never will; but I looked at some Bundesliga clubs recently and in general very few of the first team players are under 20. Also, they have a U23, and no U21. I do wonder if that is significant: do they expect players to break through at a later age than you do in England, and why?