Even the most totalitarian / authoritarian states fail to block VPNs (Russia, China, UAE...)
Plus use of a VPN is essential for some people, to access my work network for instance, I need a VPN.
VPN traffic looks just like any other encrypted traffic especially if VPN-over-HTTPS tunnel is used. And you can't block HTTPS because then you basically just blocked 99% of the internet, even poxy sites like eevblog.com. I'm looking forward to widespread rollout of DNS-over-HTTPS too which will block the last path for governments to block websites via DNS queries. Your ISP will have no idea what you're accessing, so implementing court orders becomes impossible.
I can pay for my VPN with crypto or cash. (I don't, because that would be inconvenient, but it's absolutely an option.)
About the only thing that could happen is seizure of your devices & checking what apps/programs are in use. Sure, it could happen, but we're a long way from this. Right now we have a moral panic over kids looking at boobies on the internet.
This topic of VPNs is quite complex and I have been thinking of starting a thread in the appropriate section ... but I'n sort of lazy.
I can speak about my experience in China. They do detect regular VPN connections and they allow some according to their own policies and to their policy of that day.
For example, if you travel in China with a US roaming plan you have your VPN already baked in and no problem. I suppose they figure foreigners need to access the outside world while in China. I have never had any problems using this system.
In China you can buy VPN plans. I have no personal experience but I suppose just the cost discourages the great majority of the population and the government does not need to block 100%. Most people I have talked to in China do not feel any loss by not being able to access Youtube or western social sites. They live in their own Chinese universe. If someone for some reason really needs to access the outside they can do it but that small hurdle is enough to keep the majority inside the firewall. And that is all the government wants or needs to do.
When I am in China I can access my computer desktops in Europe or US using Anydesk. No problem. I can access anything and everything with the browser, email, etc. I also leave behind my own VPN servers which are my own and not on any list of known VPN services. I can connect to these VPN servers (using OpenVPN) but the connection is so slow as to be unusable. The Chinese firewall detects it is VPN traffic and slows it down drastically. I suppose it detects the Open VPN protocol.
So, for my next visit I was thinking of studying the possibility of somehow cloaking the VPN traffic but it requires studying the issue and it is probably more complicated than it is worth my effort. I would need to modify the servers and the clients' softwares.
As I am using Open VPN I was also considering studying WireGuard but I am further put off by the fact that Linux Mint Network Manager does not natively support Wireguard.
At any rate, it seems VPNs are becoming more necessary for several reasons. Not only do some countries block access to some sites outside their country but also some sites block access from outside their country. Many US web sites block access from outside the US.
The Internet, which was going to unite the world, is becoming a group of isolated internet islands.