It is a problem and plays a role, then the rest of the SPA interactions are as bad. Amplified by 100+ third party scripts.
Stop building SPA, go back to HTML. Re-assess every third party. For extra performance and scaling, implement cache. Relax and see web experience healing.
There's definitely trade-offs. I actually prefer a proper SPA to pure HTML when on a slow connection and interacting with a site a lot.
Especially when trying to buy something. I much prefer to have a longer initial load and then have everything just work instead of waiting as I navigate between pages, the multi stage checkout, confirmation etc.
But yeah, if I'm just trying read a single article on a blog, preloading everything is pointless. A hybrid site with the initial page being server side rendered + progressive enhancement afterwards is theoretically optimal in my opinion.