I reported a Steam group which was only used for phishing on August 7th 2018 (and wrote a blog post about, Phishing site targeting gamblers).
I don’t know when the group started phishing it’s members or remember when the group was created but other type of groups that I have reported (neonazi for example) have gotten deleted way faster, usually within a week of report. But this group with phishing links sometimes on the group URL and always on the group announcements remained untouched for 10 months since my first report. And because of the long wait for deletion I think I managed to report the group 2-3 times after having waited several months since previous report.
Should of documented better the group creation date, active phishing link count and when the link was updated to bypass the URL filter. The only things that I know for sure are that the group only had one administrator user, no moderators and more than 5 unique phishing links in total. And the administrator user of the group had a normal Steam profile and played games regularly without any fear of getting banned it seemed.