It's not just about cookies but also about fingerprinting, which is extremely hard to prevent.

No extensions that randomly change your fingerprint? I suppose that might trigger a lot of captchas.

	▲	majorchord an hour ago \| parent \| next [-]
		There are but I'm not aware of anything that can reliably fool creepjs. https://abrahamjuliot.github.io/creepjs/ And yes it often results in endless captcha loops.
	▲	fsflover 9 minutes ago \| parent \| prev [-]
		Fingerprinting can be extremely sophisticated. Have a look at this test: https://coveryourtracks.eff.org/ Only Tor Browser can reliably fight with it.