PotPlayer had tried to include ads in it's installer in the past, now that has been removed. Currently there's a pop-up with it's logo that appears during the first time Player is launched after system restart. It doesn't happen every single time. There's a good chance that it might place an ad in the future inside the pop-up, but not yet. On Videohelp, there used to be ad-free versions of the player, when it started including ads in the installer, but now there isn't because there's no more ads in the installer.
I believe that if you block PotPlayerMini.exe then you disable the feature to. search and download subtitles. If you block the installer from accessing the internet, then you fail to download OpenCodec which is required to download proprietary .h265 codec for playback. Even with all the nuances it's still arguably the best video player out there at the moment by a long mile.