Why are there no big artists doing protest songs ?

Because “Killing in the Name Of” is still relevant.
- Take a Bow by Muse works almost too perfectly, too
- some of those that work forces

Big popular artist are probably pretty controlled in what the money lets them do. More independent artist are making the songs.

Big artists are performing clowns for monopoly capitalists.
- This. Especially these morons rapping about "the Man keeping them down" when they're literally working FOR "the man" and they're covered in gold bling. Congratulations. You just made a bunch of rich, white record executives even richer, while doing NOTHING for the people you claim to care about.

This isn't the 90's or 00's. Rebellion against the system is no longer the "cool" theme for artists to make money on.
- I just want angry punk to have a major comeback
- I mean, not yet. Give it a few months.

Big artists benefit too much from the system. People seem to give passes to the rich they like, but they're all our enemies. No amount of good they could possibly do would offset the support and participation they provide to this machine of destruction.

They are not on your side. That's why punk and hardcore is a thing and "pop" is garbage

I'm assuming you're talking about the US leadership? Eminem has been putting out music critical of every (2) Republican president since getting big.

There were a lot of protest songs about Iraq and then it just seemed to fizzle out

There don't have to be any protest songs. The message could be carried by another medium.
I also think right now that there is a period of uncertainty and intimidation going on. No industry wants to step into the limelight speaking up against the magas for fear of direct reprisals from the government or from those who really like it or having their attorneys targeted. So maybe the big kahunas of the music industry are less inclined to publish protest songs when they know an orange sh!tstorm will come their way when they do.
It may also be too early for any protest song to be written, recorded, and to have gained enough traction for anyone to notice.

They value not being a target. Their sponsors definitely value not being a target.

Record companies are just big corporate conflomerates, who dont want to make waves, and they control the artists' output.
Any Resistance Music is going to come from truly independent artists, and we should do everything we can to promote them.

I've heard of one big protest song by a pretty mainstream artist which didn't autofill on youtube when I just searched for it and was apparently buried. I wonder how many other songs were buried.

because they're rich and don't want to alienate any portion of people that make them more rich? Also they aren't even slightly inconvenienced by the changes in policy.
Artists reciprocating the feelings of the people is a thing of the past.