I`ve seen enough of Barker to think he wont make it. I do agree that talent like Sancho, Diaz, Foden, Smith, and the like should be constantly tested at a higher level otherwise there`s a good chance they`ll wither on the vine.
You might say that now, but you can't have had that opinion of Barker back in 2014/15 when he was constantly a threat. He'd manage to take players on the outside and get a cross in, and he also wasn't afraid to shoot and had an excellent shot on him, whether cutting inside or running around the full back and then opening his body to shoot across goal. You don't need many tricks if you can throw a step over, knock the ball past the opposing defender and run onto it.
I remember Barker being excellent when we beat Schalke 5-1. We then got them in the Youth CL knockouts and I thought we'd turn them over again. We dominated but they had one player that really impressed me throughout, he was similar to Barker in his ability to get on the ball and drive forward. At that stage I'd have put them pretty much neck and neck for talent - Barker possibly being better in my opinion (granted I'd seen Sane once). Barker then stalled, whether his own issues or the fact the club didn't give him a chance when he was in such fine form. Sane on the other hand got opportunities and then commanded a huge transfer fee and is excellent.
It's not black and white at youth level. Some young players take years to develop. Attitude, commitment, maturity, physicality all come into it. You get players like Rooney who are just ready when they're 16. That's rare. Foden, Diaz, Sancho and Smith look absolutely brilliant and need to be involved with the first team to really push on. Garcia looks class though and for me is still not getting enough game time. I see very little reason as to why he can't be a first team player, or in that first 11 when we need a DM. He is a Pep player, excellent on the ball, great range of passing and a footballing intelligence.
We need a clear out this summer. From the first team, from the EDS (and those on loan) and we need to be thinking a) who from the academy can in this moment contribute to our first team squad and; b) who from the academy could do in a year or two years or more. Our academy is working well, the top U18s are playing in the ages above to get more experience and to get used to the physicality. The main obstacles are players like Clichy, Sagna, Delph, Fernando and we need to be cut throat and get rid.
I would like to see Pep promote 4-5 academy players this summer and then buy some more experienced players to compliment them. Garcia and a new DM. Maffeo and a new RB for example. Diaz, Sancho, Foden etc might be okay with another season in the academy, at EDS level, but they should be involved in more first team squads next season to then step up. Jesus/Aguero, Sancho/Sane, Sterling/Roberts, Silva/Foden, De Bruyne/Diaz. It's a squad I'd love to see given a chance! I might be dreaming though but if one or two can make it then that's great - they just need a chance.