Don't be all gloom and doom. I agree with your parent comment that it's a reasonable law, and the general sentiment that it's manageable both when you're small (not a lot of overhead in collecting one user's stuff and shipping it) and when you're large (automate all the things). And I don't think that many requests will come in, even while the new law is still hot.

Also, 99% of the law already exists in the Netherlands. I did my first request last week actually, after I discovered a company did WiFi tracking on me. I got a reply today, very professionally and complete (and fast, I should add: they had 4 weeks). I was impressed and it gave me a lot more confidence in the company. And it didn't look like it cost them a lot of time, either.