I think it’s kind of a slippery slope; but I don’t think the search itself being login walled is apocalyptic. As long as anonymous users can clone the repositories and browse the code, I can kind of understand why they don’t want to pay to run an elastic search cluster for bots’ benefit. Presumably in-repo search could be done locally by scrapers’ hardware.
But if it turns into “login to view this repository” then GitHub will have turned evil.