I wasn't intending to get into the EU argument again. But the fact remains that there are plenty of comparisons to be drawn between the two. A smaller entity within a larger one feels that its voice is being suppressed and that decisions it has, in many cases, explicitly voted against are nevertheless being imposed on it. The legal question is harder to address although as a matter of fact some recent pieces of Brexit legislation, where they touch on Scotland, have handed powers to Westminster in favour of Holyrood. I can't be more specific as the legislation isn't opening but I well remember this debate at the time that the EU Withdrawal Acts 2018 and 2020 were being passed; I'll try to be more specific later.
All I'm saying is that you can get some way towards understanding why the Scottish may wish to leave and go their own way by articulating your reasons for wishing to leave the EU. The two are comparable as matters of emotion and philosophy -- and in turn that addresses the economic point. It may be, and probably is, the case that Scotland (and the rest of the UK) would be damaged by Scotland leaving, but the message of 2016 should surely be that warnings of economic pain will be ignored in questions such as this, either because they aren't believed or because they are judged a price worth paying to reassert sovereignty.