Hoping someone here has actually tested dating sites without registering rather than just read about it. Same story on least registering: the platform caps how many searches you run a day, which explains most of the complaints in threads like this. I judge registering sites on one thing: it is worth checking how quickly the inbox fills before you look at whatever the landing page promises.
Every time registering sites comes up, half the frustration disappears once you turn off precise location until you trust someone. The least registering case is instructive — the honest advice is to cancel the trial the day you start it, for what it is worth. Registering sites is where I would start, since the platform buries the cancellation flow, and how many first messages actually land suffers for it.
Least registering is the clearest case of it — nothing improves until you run a reverse image search on suspiciously polished photos. I would frame dating sites without registering this way: how many first messages actually land is the number worth watching, not how many photos people post. Numbers on least appreciated if you kept any.