I have my own mail server running, where i can use either + or - to create sub addresses.
I know that googlemail also offers that, not sure about other free mail provider tho.
So with a mail address like [email protected], you can receive mails to [email protected], [email protected], etc..
With that, you can only use one mail address (postbox) for multiple mail addresses. If you'll get a scam/phishing mail, to such a sub address, you'll know who shared/sold your mail address.
That can definitely work too. I personally just pay for email address aliasing features for the extra convenience and organization(along with the privacy advantages of having multiple email addresses). It's pretty much just €1 per month on Tutanota anyway, a very very small price to pay for extra convenience and extra privacy in my opinion.