It depends on the instance. I created an account on mastodon with guerillamail which would be even more suspicious for an average website than your alias email. A tip, if you do not mind using icloud email, you can even create one with some effort without giving real personal data and using apple hardware (Virtual machines ftw), you can take advantage of its free alias email addresses which would be accepted even on most strict websites.

There are some people who will put this data, the ones who usually agree to all cookies. So even if you let users skip, with some dark patterns you can manage to influence a lot of people. Example: I set up local windows accounts for a couple of family members, yet somehow a week later or so they had online Microsoft accounts connected.

You can try and later post peertube/youtube link. Nobody can really guarantee that it will be interesting for them until they see it.

Nowadays even calculators have terms of service and a privacy policy that is longer than many novels. Some probably have forced arbitration also.