I wonder whether this is a result of market conditions, or whether GitHub sees this is a first-to-market play of some sort, or whether it's something else. I hate to be a cynic given how much good Microsoft + GitHub have been doing lately, but what prevents this change from being rolled back?
Congrats again! I love using GitHub and look forward to many happy years shipping code on the platform.
Git is open source and widely supported, which doesn't benefit Microsoft. By causing GitHub-specific features to be an essential part of a "modern" or "industry standard" git workflow, they can capture more marketshare/attention, and cause alternatives to be sidelined. This requires removing all friction to entering the proprietary ecosystem, including purchasing. This, along with the acquisition of NPM, is the "embrace" part.
The next will be an expansion of GitHub and NPM's featuresets in ways that are only accessible via branded, first party tools (i.e. not git/ssh/yarn). GitHub has already made some inroads there prior to the Microsoft acquisition with of course the ubiquitous PRs as well as GitHub Issues and Actions. I imagine the ability to check out GitHub wikis as git repos will probably eventually go away to further this.
The last part ("extinguish") is turning off support for non-firstparty tools like git-via-ssh, .patch URL support, issue collaboration via email, yarn, et c. By the time they do this, few people will notice, having acclimated to the entirely-proprietary ecosystem they've been incrementally subjected to.
The goal, as always: a Microsoft editor (VS Code or Atom), editing code in a Microsoft language (TypeScript/.NET/whatever), signed off via Microsoft review software (GitHub mobile), publishing to a Microsoft website (GitHub/npm), running CI on a Microsoft VM (GitHub Actions), pushing code to a Microsoft datacenter (Azure).
It's simply a moat to prevent open, unfettered competition in any intersection of the vertical. Any weak spots (such as GitHub signup friction) are to be subsidized as they will yield benefits when later used as a cohesive whole in an anticompetitive fashion.
It's also to note they attacking on two fronts, the open source and startup folks (VS code, github, typescrip, azure) , and the enterprise with communication, productivity tools and cloud infra (Teams, Office 365, Azure)
Owned.