Physic changes the older you get, just look at Kane now compared to when he first broke into the team, or for an even better example take a look at Dele, completely different. Why do you think Chiellini's physic is wrong for a CB or Bonucci's (just 2cm's shorter) who both have identic physic's to that of Foyth? What's wrong with another of the World best CB's physic in Godin's (at 33 he's only one or two KG's heavier)?
You are utterly mad if you think Foyth has poor technique, that's EXACTLY what he possesses, his technique is his biggest strength right now, it's what makes him stand out. The kid is a baller.
But this isn't the point, players ability can and is always debated. The main point I'm making with you is that you absolutely do not change your view, despite all evidence be that both anecdotal and factual you're presented with, rather than hold your hands up, you doubled down on that opinion and it entrenched you further and further into a hole that you couldn't get out of, it ended you and made you look a bit of a tit (you can't deny this).
Yet, despite this, it sounds as you are ready to go all in on Foyth now, why? He's 21yrs old!!! Why are you convincing yourself that because his physic isn't right (despite sharing almost identical physics as the world s best CB's) that he's not going to make it? At least learn from what you've experienced and go with it. Don't claim he's gonna be World Class, don't claim he's gonna be shit, just be excited by getting the chance to watch a player play and learn his craft. If he makes it you will enjoy it more, why? Because the alternative is whilst everyone is celebrating his prowess you'll be claiming he's shit from your hole in the ground because the lad's physic isn't right.