>Why isn't there a solid alternative offering yet?
The latest version of recaptcha doesn't even prompt users. It loads on the front-end and uses a scoring system. It's likely you've used it but didn't even know because it's invisible.
It's the older implementations that have the slow loading images.
On Google Chrome, with adblock on, without my Google account signed in, in a new incognito tab with no extensions, I have the experience of it being invisible. When I go back to the same site on Firefox, logged onto my Google account, no adblock on, no privacy options on, I have to identify dozens of photos.
As far as I can tell, it just checks to see if your browser is Google Chrome to give you your score.
Not really. Thats if the developers code it so that if you get a low score -> trigger images captcha (recaptcha v2)
Recatpcha v3 by itself NEVER shows anything to the user and its entirely up the application itself on how to deal with users who are likely to be bots (which also includes users with anti-fingerprinting measures)
Kicking """questionable""" users off the site entirely is not a "solid alternative".
This is just splitting recaptcha into two pieces and giving you the first half. Okay, fine, but it's the second half that was causing all the problems!
The latest version of recaptcha doesn't even prompt users. It loads on the front-end and uses a scoring system. It's likely you've used it but didn't even know because it's invisible.
It's the older implementations that have the slow loading images.