I'm not sure it's junior/senior so much as personal taste: Plenty of junior engineers use Vim and Emacs, neither of which are trendy in any meaningful way, and I'm sure there are senior engineers who use Visual Studio with all of its whiz-bang. Similarly with websites, some have ideas which need AJAX and, possibly, WASM, and others have ideas which need static sites or, at most, "slightly dynamic" websites with only a little JS mutating the DOM.

More specifically, it isn't always up to the engineers:

> We need to build a basic company website.

Marketing is inherently trendy and the people designing the website, as in dictating what it needs to do and look like, are the marketers, who are influenced by the "cool" websites they've seen. Marketers follow trends. It isn't really negotiable in that profession. The engineers do their best to deliver on what marketing wants, and if that requires a WASM re-implementation of NyanCat to prove that we're retro-hip and DownToFax, so be it.