It's not his fault. I just think it all depends on how you assess "value". To me, if your team is garbage, what was the value in your production?Why is it Trout's fault that other 24 guys on his team sucked (on the whole)?
A lot of voters feel the same way. It's not the player of the year award, or best statistical season award. I think Mookie has a shot to win it because his team won their division.
For the record, it's why I hate MVP awards in general. Player of the year would probably be Trout, though Betts and maybe even Altuve definitely deserve consideration.