Cameras in general aren't as easy as cheap plugs to deal with. There's the OpenIPC project but it seems only to support very specific chips that are sometimes older, hard to find or not price/feature competitive like something such as what TP-Link offers.

For what's worth TP-Link Tapo cameras (TC70, 71 etc.) aren't that bad when it comes to privacy, there isn't much "cloud". They do require you to use their mobile app and cloud to setup the camera but afterwards you can just run them on an isolated VLAN / firewall them from the internet completely and you'll still be able to use all of the camera's features. Those cameras provide a generic rtsp stream that even VLC can play and there's also a good HA integration that provides all features of the TP-Link Tapo application like pan / move / download recordings from the camera's SD card and whatnot 100% locally / offline.

I particularly like their cameras because they're really cheap and decent, while not perfect in terms of privacy they've a good trade off when it comes to price but require initial cloud setup. They also have wireless versions, ethernet versions and a cheap PoE splitter will be good for those.