If they deserve praise for the successful years, then they should should criticism for the current mess.
Yes that's fair - but if you're balancing the scales between the success they've brought to the club Vs the 'mess' we are in now, then the plus side massively, massively outweighs the negative still. Surely there can't be any argument over that?
(This is an internet forum, of course there is argument over that - but objectively there isn't)
Especially if you weigh the current mess Vs most of our other non-KP Premier League existence.