That's not reCAPTCHA's fault. It happens when you pass a challenge and the website decides that's not good enough and to serve you another one. I'm sure services like Cloudflare invalidates solved challenges if you're still too suspicious, even immediately, and that's probably the root of the problem.
Their overbroad definition of suspicious is what's suspicious to me. Literally if I were to use a Private Window, I'd get it.
These days you're suspicious whenever you're not rocking the usual spyware and telemetry. Especially if there's any chance that any of the software you're running is possible to modify (even if it hasn't been).
You still have those? I've not seen them in a long time.
I fully expect it if I were to use a Private Window.