This is a really disingenuous point as is Scotland voted to remain etc.
The vote was a national vote, it was not constituency based and that combination of voting systems really is irrelevant to the outcome. If it was constituency based as it could have been and delegates were elected on a one off special basis then Brexit would have been enacted with no problem. However at the general election people did not vote just on the basis of leave or remain. There were other factors that people considered to be more important. For instance, myself would always vote on the whole manifesto and especially the health policies and the brexit question was irrelevant to me