Because if the knots argument is correct- there is a risk that more csam images will be mined in Bitcoin due to this change in mempool policy.

That will be brand damage / legal risk and affects all users if more csam ends up in blocks permanently.

So that’s why it affects everyone.

And it’s up to the devs to do risk/reward analysis and prove why any changes from the status quo are required.

If they fail in that job, they will be replaced- which looks like the path we are headed towards.