First of all, I’m assuming you don’t have a google sheet as you mentioned that you are using a glide table, so that’s why you are trying to perform an array formula in within glide.
I didn’t mean you having to manually copying the email into each row. I meant an action in your app that gets triggered whenever the user does something, such as pressing a button. That’s when the column would be filled through a set column action. Possibly through some on onboarding workflow.
The fact that you can’t apply row owners to computed columns is intentional, but has nothing to do with anything like GDPR…mostly. It’s more to do with data security in general. It’s that fact that computed columns are computed directly on the user device. Not on the glide server. You have to send data to the user before any computations can occur. If you would be allowed to send your entire database to a random user, just so a computed column can check who is the row owner, then you have already breached security by sending out all data for all rows instead of only the data that belongs to the owners of each row.
It’s like a bank handing over the account information for every single one of their customers and then saying “just look for only your own account”. Some people might be honest, but others won’t and will steal everybody’s information and money because they had access to it. Instead, something needs to occur at the bank so they only hand over your account information to only you. That’s where row owners come in. The server is the bank and determines which information should be sent to the user. If the server sent all of the information to the user and the user had to decide which pieces of information belonged to them, then what’s the point of data security. Computed columns are the same as the user making the decisions with the data. Not the server. How that makes sense.