If it was done in a year or immediately after gaining huge momentum, then sure we'll listen, but again, GitHub has been around for so long that it's clear they simply couldn't predict the growth and handle the increase in cost.
I believe it is an opportunistic bait-and-switch.
I don't know exactly what's going on at GitLab, but this is a classic pattern when the motivations of founders ("Let's make something cool to help other coders, and make a buck in the process") are supplanted by the motivations of VCs ("Fuck the coders, lets make as much money as possible in the term.")
Edit: Can add to that second sentence "...and exit just after the profits tick-up, but before the market has enough time to migrate off our platform.")
The goal of which is to seek monopoly or at worst stable oligopoly.
Anyway, GP was asking what you call it when you saturate/dominate a market, become the standard and then raise prices on your captured audience. This is definitional monopoly. VC-backed capitalism is a predictable symptom emerging from the possbility of such outcomes.
Users are absolutely right to be upset at Gitlab, Docker, etc. who pull a bait-and-switch on the community. Users adopt the product because of the infra foundation is free, and then comes the rug pull when the product reaches market saturation.
This almost always happens right after a capital raise...