One is run in the cloud while the other is run from your location on the net using your browser. So yes there will be differences just from a network perspective. For a full breakdown on differences review About PageSpeed Insights | Google Developers
It is not a question of trust. I use both for analysis. I more frequently use lighthouse because I do lots of local development but page speed insights uses a broader data set which I can’t easily emulate.
The most important things you can do to get your score up with Webflow sites is optimize your images, if you use Google fonts then download the fonts, upload them to Webflow and ditch the webfont loader.
I tried this today before your post and it does clear an issue or two but it actually took a lot longer to load a woff file from webflow so I went back to google fonts. So might be worth a revisit?