I changed my own internal concept of a boycott.

I used to think, "I'll stop shopping here! They'll change their policies!", and yeah, nope, what happens is the company just leans into the customers that remained. So my "boycott" didn't do anything but deprive me of something I wanted.

However, I decided that, at least for a certain set of things, my desire for the thing can be outweighed by my desire not to contribute to something.

So boycott's aren't about me changing a company's policies, they're about me allocating my resources towards the things I want to see in the world.

What is today and who do I blame for it

It's not debatable. Though it is being debated by people who want that to be the case because racism.

It is not valid.

Why not? Why is a bad thing?