SEMRush pulled up that our site needed to minify JavaScript and CSS files and reduce render-blocking resources. I tried to remedy this by downloading the auto optimise plug in for WordPress and tried several different configurations, based on YT videos and blogs However, I tested the Google Lighthouse performance score afterwards, and it declined in all configurations compared with our baseline, where no plugin was active.

A few questions:

1- Are Google Lighthouse scores reliable in this case? Should I expect google lighthouse scores to improve once I've minified the files and removed render-blocking resources?

2- What action would you take next? Should I continue trying out different configurations, pass to a developer or accept that our Word Press theme is not the best and we may need a complete site rebuild to solve this issue?