the Theme only requests jQuery if you’re either the Sticky Navigation or Blog Masonry options. Both of which will be replaced with vanilla JS in a near future update.
If neither option is enabled then other plugins are requesting jQuery – and you would need to replace those plugins.
I think the issue with that pagespeed report is to do with Googles server locations.
If you test your site on GT Metrix – and choose a Canada/US server ( Google server locations ) you will see a much slower time then if you test it on a UK server.
Once google collects some real world data you should see a significant improvement on those metrics.