No, before the remote pass they had to pay a one-time fee, but since they added the remote pass subscription as long as the plex server admin has a plex pass no-one has to pay a cent.

https://support.plex.tv/articles/requirements-for-remote-playback-of-personal-media/

Since 2025-04-29, there are new requirements for allowing remote playback of video personal media from a Plex Media Server (that is, streaming when not on the same local network as the server). These requirements apply to apps that have been updated to our new experience, such as our mobile app, and will also apply to other platforms as we progress.

When using an affected app/platform to stream personal video content remotely from a Plex Media Server, then one of the following needs to be true:

• The admin account for the Plex Media Server has an active Plex Pass (which also allows remote playback for any other user streaming from that server)

• Your account has an active Plex Pass

• Your account has an active Remote Watch Pass

but just those should be safe enough if your users aren’t reusing passwords.

So you’ve put your server/networks security in the hands of 17 other people’s password policies, and you think that’s “actually safe to do so if proper precautions are taken”?

I’ve got 20+ friends and family who use my Plex server, only a few have ever paid a cent (when they had the one time fee for mobile streaming), and my server and networks security is not at the risk of someone using the password “password”.