As someone who runs his own consulting business, if I had clients who didn't know what they were doing and abusive towards me, I'd drop them in a heartbeat. The original poster on reddit isn't going to garner any sympathy from me.
I tried to downgrade my bitbucket subscription to the free plan back before they sold the company, but when I did I just got some error back saying that paypal couldn't charge me 0 dollars.
So I filled a bug, tried again a month or so later and when I still couldn't unsubscribe (I wasn't the only one who had that problem, two others also commented on the bug) sent him a very nasty email, threatening to report him to paypal as a fraudster (impossible to end subscriptions would be a classic fraud technique).
If he had brushed me of rather than told me that I needed to turn of the subscription from paypal I might have ended it right there.
Instead I dragged two other people into it.