PowerDeleteSuite is pretty easy, however it doesn't get everything - reddit limits the number of comments you can see on your profile. For example, if you look at one of your older top comments, after PDS does its stuff it will get rid of the top comment, but it will leave behind any low karma replies underneath.

Shreddit can take the GDPR csv files as an input, then it will go through and delete everything. You should use the github version rather than the website. However, you need the GDPR files to begin with, and it uses the API so it won't work after 1 July. Reddit seem to have been stalling on delivering GDPR files for exactly this reason.