CapnZapp
Legend
Yes - you know your group best. If your fighter player is perfectly content sitting on his hands during the fight where you dazzle everybody with you fantastical magic, you should definitely do that.Concentration. Most of your best spells require it, including fun high level spells. If you're forced to not use spells in order to make sure that the Fighter has a magic weapon for 1 hour at a time, it's a little more than "I don't feel like it". It's more like "I may need to be doing other things".
Myself... I don't know. If I knew the campaign would have no items, and I still created a wizard character... I would probably realize ahead of time that I would contribute to the net sum of fun for the group if I reserved my concentration spot for the fighter... just once in a while.
But you do you.