Well that goes without saying. He was injured on the pitch and still under contract. I suppose we'll see, but I'd be surprised if they pull that offer. 15 mil or so? That's peanuts compared to the good will it would show to everyone, including potential future signings. Regardless, I just hope the best for him. He's been great to watch.
Firstly, £15m is not peanuts ffs. That's borderline insulting.
Secondly, players that don't sign long term deals take a risk with a huge potential upside and downside. The upside is that they can request massive sign-on fees. For example even Adnan Januzaj, when his contract was expiring, received a £5m sign-on fee (and £60k pw salary!). Otherwise another club could have offered him that money and signed him on Bosman. You can bet Zlatan received a big sign-on fee as a result of running his contract down at PSG, maybe even a fee as big as his annual salary. That's the upside of short-term contracts. The downside is obviously that you are not protected, in case of injuries and so on.
You can't take the upside without the downside. United, or any football club, is not a charity. Footballers are paid extremely handsomely, there is no moral obligation by the clubs to offer them £250kpw contracts just as a "thank you for the good times" when it makes 0 commercial sense. It's a business after all. The type of business that made Wayne Rooney twice put in a transfer request and hold the club to ransom in order to get paid on a par with the best players in the world. And you want to show the players "good will"? There is no emotion in business. End of.
If (not been confirmed yet) Zlatan did do his ligaments, then I do feel sorry for him and wish him a speedy recovery. It'd be very sad if last night was his last match for United, it shouldn't be this way. But we shouldn't be offering a 35yo with ligament damage a contract extension, ffs.