After watching the video (which was pretty good), I have to say that Becton will not be written off by the team. What might end up happening is that he gets moved to RT. But he'll have a starting spot on the roster. And if gets moved to RT, he'll make All-Pro sooner or later.
How man years should you give a player to prove himself? There's not fixed answer to that question. The team has needs in the off-season and at draft-time. And the most glaring needs are addressed first. So it depends on how glaring the weakness is. Take for instance Mims. He needs to show himself to be better than Walker. He is also competing against Davis who was picked right before Jamal Adams. If all these guys suck, there will be a WR pick early in the 2023 draft.