I would never do that. It teaches people to accept invalid certification certs. We used to do that 10 years ago, but it’s unnecessary. I run the PKI environment for my company, just costs some hardened VMs and a USB stick. Things like “let’s encrypt” make valid certs free.
The problem with certs is that you have to have names, and making that work isn’t easy. Most people probably don’t run internal dns servers, nor do they run hairpin NAT on their external interface.
I still say there is no reason for TLS on this service. If the service were exploitable, it’s just as exploitable encrypted.
Let people snoop my football game I’m watching in my hotel room.
If i were passing credentials or credit card data, or my porn preferences, then it would need to be encrypted. That’s why they encrypt that.
Everyone is happy to pass data to hosted servers in big data centers, but they don’t consider the fact that alot of those services still only encrypt the edge, and once the data is internal to their network, it often goes plain text over a network or server shared by hundreds of different customers.
Sooner or later all your traffic will be MITM by your provider when they require you to trust one of their self-signed CA certs. It’s really coming.