Listening to the video, I believe one of the lords mentioned they had done just that - pardon all the people convicted by that law who were still alive today. I'll try to find a news reference.

The question, now, is whether to posthumously pardon the others.

Update: Found an article. Turns out they haven't been pardoned, but their convictions are now "disregarded" and no longer appear on their criminal record[1].

[1] https://www.gov.uk/government/news/historic-convictions-for-...