~Snip
Garnacho and Kobbie Mainoo are youth players that Man United should really retain at this time because both of them have very good potential to become big players and will be a strong support for Ten Hag's long-term plans. Even though Man United is having a headache about their small budget for next season but I think they won't just let Garnacho and Mainoo go because they can clearly make a big contribution to Man United, and in the next few years, the two young players are likely to have high market value.
You're right, Manchester United are unlikely to throw away talented young players early just to get better players based on one or two people's judgment. Garnacho and Mainoo are two young talents who really deserve to be included in Ten Hag's plans, so it would be best if they were not for sale.
If Ten Hag really needs more experienced players to support his plans next season, I tend to choose Rashford and Antony to be sold. These two players really don't impress enough to stay longer, but perhaps Manchester United management and Ten Hag have different plans. I think Manchester United need good defenders and midfielders, but Mainoo has a good future to look forward to.