For me Scrum is too formal, too many rules to do agile. Sometimes taking it to the bureaucratic extreme.
But on the other side there are also agile advocates, for whom there exist almost no rules. Everything should be agile!
I read the following quote:
"We can't look into the future. No one knows what's right for the end user/customer until we put the product in their hands and get some feedback."
This for me is a very extreme view. That dismisses all the knowledge that domain experts have, experience that business analysts and developers have.
Some of the best software is made by developers that made it for themself.
Yes, customer feedback is important, but sometimes customers don't know they needed something, until somebody created it and shared it with them.