Just thought I'd share.
I've been fighting RTSP streaming reliability since I started into this a few years ago with ST and now Hubitat. I am very happy to say I finally have it working to what I consider acceptable with one smallish change. This may be obvious to some but it wasn't to me until I did it. I've always used Raspberry Pi's as my TinyCam servers and tried other Android hosts along the way from tables to TV Boxes with multiple configuration variables.. The result was pretty much the same, freezing, skipped frames, slow response. The same things I see others complain about.
My change was simple. I've been using a Lenovo FDH table as my "display" tablet with the TinyCam server on 2 separate RPi's. I moved the TinyCam server to the same Lenovo tablet I use as the display tablet. I've tried it with using the video stream address as the loop back address (127.0.0.1) and the a actual IP address of the tablet and can't really see a difference. I don't truly understand the difference so I won't expand on that.
I always though the single table running both applications was stretching the HP available and separating them to different machines was the obvious thing to do. Guess I was wrong there. The difference is night and day. I think some of the difference is obviously the tablet has more HP but I've tried putting on a similar tablet before that was separate from the display tablet with not so great results.
A second thing I did some time ago that gave me a little improvement at the time was to use a separate 2.4 GHZ only router connected via cable to the main router to create a separate 2.4 GHz network for the cameras to connect to. I did that because I read someplace that most of these cheap WiFi cameras use a chipset that is 2.4and 5.0 capable but the software only addresses the 2.4 capabilities. As a result, the hardware is always doing this back and forth thing between the two frequencies causing problems. On the forum I read it on, it caused quite a bit is disagreement and discussion. Not sure if the reasoning is correct but it did help for me.
Hope this helps.