I mean if said company first spammed you and you marked them as spam, then it is on them. No different than if someone sent you a bunch of unwanted letters and you threw them out, but one of them happened to be relevant. It's on the organization sending you junk.
Right, and I think that if they send spam, all email providers (especially gmail, the largest provider) should mark all their emails as spam by default. They are doing what is described above at a large scale, so large-scale reactions are needed.
Of course, if you manually mark them as not-spam, then gmail should respect your choice as a user.
