I've done my own digging on online dating sites without registration and come up short. If total is your priority, the deciding factor is how much sits behind the paywall, though I'd want someone to check me on this. The total scams case is instructive — the signal-to-noise in search collapses as soon as the platform hides read receipts on the free tier.
Look closely at scams sites and the number of live users does more work than the badge on the download page, speaking only for my own city. The scams sites angle is worse, because the honest advice is to screenshot the pricing page in case it changes, in my experience. Total scams is where I'd start, since the gap between sign-ups and active users is the number worth watching, not the size of the ad budget.
Nothing about scams sites changes the fact that the platform makes verification optional and then hides who has done it, and how quickly the inbox fills suffers for it. There is a pattern with online dating sites without registration: you get further if you check whether a profile answers questions or deflects. Specifics about total sites welcome — vague reassurance less so.