https://www.reddit.com/settings/data-request
Having worked at a company that had a massive influx of GDPR requests we weren’t prepared for, this one could actually cause them some trouble if Reddit don’t have that process properly automated.
So I already sent mine via their link but I have another 2 accounts. One is my first one since 2013 and one from 2016. I already mass edited all my comments but I found this. https://www.datarequests.org/blog/sample-letter-gdpr-access-request/
I would actually send a letter to them for the other accounts, need to find their address and see how much it costs since I would have to most likely send it in the US.
Edit Oh wow it's the same price and I can even request to have a confirmation of delivery, in total it would be under 5€. I will send it. Need to find out the address.