> but most modern WordPress development, especially Gutenberg — is really JavaScript
As are probably most other discussed ecosystems in this thread. Most people doing Go for web development are probably writing JS heavy front-ends which interact with API endpoints on the Go driven back-end.
> If/when PHP becomes just a legacy part of WordPress, it’ll be interesting to see what impact (of any) that has on the languages perception.
What would it be replaced with and why?
Gutenberg still interacts with a PHP back-end. There will always (until web drastically changes) be a need for something to do the API handling. Would Automattic push the community to build that back-end using Go? Node?
In fact, I would posit that many of the complaints about PHP come from WordPress’s widespread usage and its slowness to adopt modern PHP features (and to be fair, I do understand that slowness. If you power such a huge portion of the web, making breaking changes to things that could impact tens of millions of sites on the name of modernization is difficult to reconcile). If/when PHP becomes just a legacy part of WordPress, it’ll be interesting to see what impact (of any) that has on the languages perception.