If you look at cwvtech.report you’ll see that in the last year, sites on Wix and Squarespace on average have improved their site speed more than WordPress sites. WordPress has a performance team now, and it has made some progress. But the reality is that it hasn’t really made big strides yet, and in my opinion, really should. Project leadership still seems unwilling to focus on performance though, which has to do with the next point:

WordPress’ full site editing project is not done yet. Anecdotally, more and more people are having a hard time deciding how to build their site on WordPress. Wix and Squarespace are simply way simpler tools to build a site. As they improve their SEO tooling, there’s less and less reason to switch over to WordPress.