Beg to differ. He was mostly excellent through his first two seasons with us and it was almost unanimously felt on the Caf that his injury before the Europa League final was the reason we did not win.
Interesting, I can only say I wasn't under that impression. I'd give you that he looked pretty good in the 1st half of the first season and iirc he ended his first year with an overall good to very good season but excellent seems like big push to me. I think, the calamities started to appear in season 2 after all the Greece hassle (or was that in season 1?). That being said, I've learned not to give too much weight on such wording like excellent or very good - I am not the most enthusiastic person so better not to argue about that.
I also can't really remember that his injury was used as some sort of explanation for the EL loss. I mean, we didn't manage to score against this lot (or not more than once at least) when we were player for player the better team. Having Maguire or not wouldn't have changed that at all. But I guess, it has been turbulent times back then with Ole wars in full flow.
He was fine when called upon last year and has looked good so far in pre season, not to mention his continuing good form at International level. He would instantly be West Hams best defender by some margin should they sign him and the same applies to a whole host of clubs including Tottenham and Villa. His asking price at 40M is clearly a starting point for negotiations but he is worth 30M to 35M easily and we would be mugs to sell him for less, particularly when we would then have to turn around and replace him.
Being fine and looking good in three pre season games isn't a lot... He is a CB who was at fault for multiple clangers, people will always remember such an incident longer than him "being fine" in a few outings here and there.
Don't get me wrong, I don't want to sh** on the player. I am happy to watch him resurrect his player carreer. But his time for us is done, he is on wages nobody would pay him and the manager doesn't really value him. He is also not at all something that you would call a modern CB. He has a reputation to be able to cause irritation and he seems to have a pretty bad ability to judge his own limitations. That isn't a great combination. If we keep him for another year because we insist on 5 million, we might even get less next summer.
edit: the take with "he becomes instantly Westhams best defender" - I don't think I'd buy that. The guy hasn't played a lot last year, has still received some flak (even if some of it might have been overly harsh), the season before was really bad (reasons are not of interest for buyers today) and the season before the problems started. So who knows what kind of player he actually is today? I'd be not so sure about him being even the player we bought from Leicester. He was limited already back then. But now he is even older and his confidence is shot (at least it should be, if he has such a high opinion of himself, as some interviews suggest, he is in trouble...)