I have seen websites where the homepage's HTML alone was over 1MB! in size. The only thing that got exited was my CPU.
Let me tell you: if you want a header with a background image where the text is aligned at the bottom you can just write:
<h1>My header</h1>
There is no need to write it as: <div id="mainHeader"><div class="align-text-bottom"><h1>My header</h1></div></div>
And if you want to stick the header to the top you can use `position: sticky` in CSS instead of including a huge Javascript file that can do all kinds of fancy stuff you don't need.But I am not sure I can blame those front-end developers. Deadlines are tight and it takes effort to learn about the technical aspects of front-end development.
My personal standard is that a page should be ready in 1 second. For huge sites 3 seconds max. I've been creating small and huge websites for over 20 years now and never had a problem with these goals. This includes webapps built with Javascript.