Sometime in 2021, Google is making a big change to its algorithm, adding what it calls "Core Web Vitals" as a ranking signal. This is, at its heart, an assesment of how swiftly your page loads from a user persepective:
- How quickly is there usable information on the page?
- How long until I can interact with this page?
It's worth thinking of this as a more sophisticated evolution of the old page speed metric. Google is now less interested in how quickly your page load completes, and more interested in how long until the reader can do eveything they want.
This is largely likely to be a technicla challenge - but you can monitor your performance using the Core Web Vital test in Search Console.