Whilst not disagreeing with you that devolution has fuelled some quite disgraceful xenophobia, it was not this that I was specifically referring to..If, by that, you mean anti-English discrimination, I'm unsurprised.
My late brother, who wed a Jock lass and went to live in Greenock while working for Cisco Systems sent me (must be nearly 20 years ago) an academic study which very carefully presented evidence showing that Jock racism against English folk living/working in Scotland had leapt out of Pandora's Box within weeks of devolution, and flourished.
My observation was that the overwhelming attitude from Whitehall has been to step back from activities in Scotland whether the issue was one which had been devolved or not. The attitude seems to be to find any excuse not to get involved and to collectively wash their hands of everything. It is particularly noticeable with the Police, where Police Scotland seem to be being allowed to behave as if they are no longer in the UK, but the same has happened with BBC Scotland and many other government agencies, who are to a great extend declaring UDI, and being allowed to do so. So many tin pot hierarchies are breeding from this single event it is quite concerning, particularly as these newly devolved agencies have neither the history nor the competence to carry out the tasks and responsibilities that they have now taken upon themselves..
I do not believe that this was ever foreseen as a consequence of devolution, but is should have done.. essentially that idiot Blair kicked off a process of structural mitosis, and who knows where it will end!