I've gotten my site down to ~0.5s load time and rank for a number of tech SERPs, still get a few thousand visits from Google per day for 5-10 year old articles: https://www.jeffgeerling.com/
SEO is overrated. Focus on high-quality content that people want to link to.
Case in point: I have a podcast (in German) whose name is a common German phrase ("Gar nicht so einfach", which translates to "Not that easy"). In SERPs for that phrase, the first few results are usually dictionaries, but my podcast's site (https://xyrillian.de/noises/gnse/) usually appears around 7th or 8th place still on the first page. This is without me doing any SEO, and in fact, without keeping up a regular schedule. >_> But the few episodes that there are have been reviewed overwhelmingly positively, and that appears to be all it takes.
