For the record, those providers already charged a significant premium for the equivalent compute you could get at Hetzner and OVH. The margins have decreased but they've had a profit margin on compute for a long time.

Yes, and they will to preserve margins at some point. They're just doing a huge Mexican standoff, waiting for others to move. All smaller clouds have raised some prices already.

They'll probably wait for summer, the world cup finals, or whatever's last big US government thing is so it flies under the radar.

Step change makes sense for a smaller provider. You bait people to build on top of you with the best prices, then rug pull and hope the switching costs and economic frictions delay the attrition.

Because heroku and aws were 10x previous hetzner price

idk if you're comparing like-for-like here. I think on EC2, other customers can balloon up to fill your idle time because they're running on the same physical hardware. What this is talking about is renting hardware that is exclusively earmarked for your usage, so your compute is not fungible with other customers. It's more correctly priced against buying your own hardware and maintaining it yourself.