Yes, I'm aware of this limitation, but PocketBase uses HTTP2 when combined with the --https flag (this is by go's default net/http implementation) so it shouldn't be too much of a concern.
I’m not fully understanding the response - are you saying that the limit is not imposed if you use https? Or am I reading wrong?
The default limit of ~100 connections should be more than enough for most applications (additionally, the JS SDK client maintains a single SSE connection for a page no matter to how many things the user has subscribed, so that also helps).
Best solution today is to move to http2 on your server -- which has an SSL (TLS 1.2) requirement.
Looks like pocketbase implements this. If you use another server, like nginx, you have to enable this for each site.