For instance, People I know that are using Eventbrite for private event registration. To sign up for the event with or without an account, you have to write and confirm your email in the boxes, I did some looking up to see if hosts can see the email. I didn't find any answers so I made a Reddit post asking, and got a reply saying "No, they can't. Eventbrite deletes them as soon as you submit the form." I wanted to be sure so I created a private test event and registered for it in a private window. I then went to my event dashboard and clicked on the ticket # where I can in fact view it (the email shown is made up).
I only asked Perplexity after trying to find out myself. It did in fact find the answer (link #8: View your Attendee Summary report): "Review attendee purchase details like email address ..." I've found LLMs and search tools like Perplexity to be unreliable for answering questions like this for websites, as well as software. Which means I may not turn to them in cases where they actually would help. It's too bad they hallucinate a lot too.
I had an incident when my barber decided to use online appointment booking using Calendy.
For reasons, I often search for some of my emails and aliases.
To my delight, my first name and an email address was publicly visible along with the conversation.
Calendy made some corrections to their service soon after.
Trust no service to be secure.
Use a disposable/junk email address that doesn't connect to anything secure or you need kept private like bank accounts etc
Why you are being downvoted is amazing. This is a legitimate question of privacy. And it's one that too many blindly trust in a service just because it says it can be trusted.
Use alias services like SimpleLogin.