Martinez likes Gibson. Alot.
So do i mate, but the simple fact is Martinez is a winner with a winenrs mentality, i don't see him being as sentimental as some managers and at the end of the day the truly best managers arent sentimental - only to the point it serves their interests usually
Problem with Gibson is you will never ever be able to build a team with him as a central part of it with any confidence due to the fitness record being what it is, it's not going to fix itself now or likely ever will do, people who think it will are like the people who thought all jela needed was a goal to get back to where he was at the start of his everton days, its a ncie sentiment and its nice to hope for it, but reality says otherwise
So the future will be him as either a squad player who can come in when fit and injuries suspensions hit - assuming he is actually fit at those times himself to do so, as a starter who we all know is likely to breakdown with a relatively long term injury at any moment, or to move him on... so its down to what Martinez sees his role as and what role Gibson is happy with going onwards
But to have a player who potentially every season you need to sign a covering player for due to them going down crocked isn't the way to build a team for the future