Because their end goal is (or was allegedly) independence, the SNP expend a lot of energy on proving they are different from Westminster and trying to emphasise the difference between Scotland and the rest of the UK. So everything that Westminster does, they have to do differently.
The SNP used to be 'the Tartan Tories' and are not especially progressive at heart. It's a strategy. I think the roots of it may have been well intentioned - in some ways a smaller country in the process of creating itself is better able to base legislation on evienced best practise. However, this has devolved rather quickly into putting a shiny spin on everything they do, forcing terrible legislation through parliament because it sounds impressive and most of all, different from what has gone before (named person, sectarian/football law/hate crime/gra).
They are seduced by the idea that anything that is different from the status quo is de facto a good thing. Wholly sold on a progressive utopia that is based on fuck all of solid theory/experience/evidence, as far as I can see.
(Meanwhile serious problems in the country's infrastructure, political and legislative structure etc are aggressively ignored, but that's another subject).