Only time I ever attempted something remotely similar was during a PoC using a specialized client device (think RF handheld) that needed to render content quick

Only time I ever attempted something remotely similar was during a PoC using a specialized client device (think RF handheld) that needed to render content quickly in a custom browser. Loading tons of dependencies was my concern. So writing custom components with pure JS was the approach BUT those components were not for rendering views and instead for initializing behavior with regard to keypress behavior per view. Attempting to render content was still done with a server side templating framework (Thymeleaf). This was eventually abandoned because development and testing cross browser (on a PC) was buggy. As many have already stated, a tutorial like this is interesting for hobby projects, but I would not adopt this approach in production. Libraries and frameworks have a lot of energy invested in them and should be considered early.