In reply to Albert.

@Albert: Do you make websites for your own use on localhost or are your sites facing any size of publicity? Or has just the web evolved and you forgot to follow trends?

Your arguments just lack ANY logic:
Bloating WP core with completely needless and unwanted stuff (like bacon emoji) or with stuff of marginal importance but no actual use (shiny updates, REST API) or with the customizer (that broke so many themes just because WP never wants to break anything) or with... well...the not so bright idea of a computing-intensive link checker that actually does not check the link for its validity does not matter as such features will keep WP core "light" for ever.

While implementation of basic features (ones that you can not afford to lack if your site is for the public) into core as optional modules would make WP "heavy", while adding the same basic features by plugins will keep your WP installation "light".