Today, we are officially introducing a proof-of-work (PoW) defense for onion services designed to prioritize verified network traffic as a deterrent against denial of service (DoS) attacks with the release of Tor 0.4.8.
This is a new PoW protocol that will be used to defend against DDOSs
Probably if your country judges illegal to connect to the tor network, but not on a VPN. Iirc, a bridge could also hide the fact that you're connecting to the tor network tho