And that's why we shouldn't give him £200k — not that we're going to. £80k is a laughable suggestion not only by United's standards though. Kamara, Tielemans are on £150k, Merino is on £130k, McGuin is on £120k, Chukwuemeka is on £100k... none of them are real stars, some of them aren't even guaranteed starters at their club. Mainoo hasn't been brilliant this season, he's been fairly underwhelming but he's still one of the brightest midfield talents in the world with enormous potential, who is signing a long-term contract (I'd imagine that we'd ask for something like 5+1).
It's not 2010 anymore. £100k is probably the low end for any notable Premier League player nowadays. He's also a homegrown player and that's suddenly a huge issue for United, especially if we'll manage to offload all of our deadwood (a lot of whom help to fill our homegrown quota — Rashford, Shaw, Mount).