Hi. This change had to do with the increasing popularity in recent years in Europe and worldwide of fully automated filling stations, such as Tanpoool24 (https://www.tankpool24.eu/, https://www.google.com/maps/search/tankpool24/@51.150486,7.7046383,8.66z), Shell etc. where labelling 24/7, cashless, with one or more fuel and payment machines, fully automatic service stations as "amenity=vending_machine" is, in my opinion, a mistake.
I edited the article https://wiki.openstreetmap.org/wiki/Tag:vending%3Dfuel in 2018, this change was made based on a discussion that took place on the previous Discord Poland forum.forum.
I have not mentioned that an automatic filling station can also, in a few cases, be part of a "traditional" filling station.