The modern SNP is fundamentally different from the Leave campaign. Their nationalism is civic and gets so much support because people are frustrated that Scotland keeps voting in progressive, redistributive politicians but it makes little difference unless the English tabloids decide they want to mix things up a bit, are frustrated that New Labour started using Scottish seats as safe havens for politicians who had nothing to do with their constituencies and didn't engage with them on massive issues like Iraq, and are frustrated that Westminster is a bad joke that's been heading for a crisis like this one for a long time. Don't get caught up on the word nationalism -- the SNP is one of the most progressive parties in the UK (at least since I moved here in 2010, can't speak about the 1970s or whatever era SNP you're talking about). They are more or less somewhere between the Greens and Kennedy-era Lib Dems on policy (and actually the Scottish Greens supported independence already the last time around and the Scottish Lib Dems only narrowly opposed it with many members campaigning for Yes anyway, so they're hardly alone).
I'm not a massive fan of the SNP and voted No in 2014 but comparing them to the absolute disgrace that was the Leave campaign is exactly the kind of attitude to Scottish politics that *actually* feeds their support, not some imagined hate of the English that could be compared to Farage's Third Reich propaganda (I mean, yeah, we "hate" the English and take the piss out of you when you lose to Iceland, but that's a fucking joke and not the reason half the country wants to break up the union FFS).
Anyway, as an EU citizen that's made Scotland my home I'm proud of the way the SNP has acted throughout this farce. I have no interest in contributing taxes to a government headed by Theresa May that uses my future as a bargaining chip so I'll campaign for and vote Yes if there's a second independence referendum. I'd rather live in a slightly poorer country where the head of the government gives speeches like
this than in such a dystopian nightmare.