25mbps down is "ok" for most tasks, but 3mbps up isn't sufficient for WFH. For interactive collaboration you want lowest latency possible and enough upload bandwidth to deliver crisp 720p footage, for eg. presentations, whiteboarding, webcam.

I have 50/20 in Australia on VDSL2, and it is just barely good enough for this. You're right about it not being consistent/maintained though. Some days I could collab remotely no worries, other days it was simply impossible.