It turns out there is a sufficient amount of immigration that is disliked by the populace that they will dump support for long-standing parties in favour of those who promise change.
In a sense, you may be correct, but who cares? The majority of people voted against xenophobia, some people are still super xenophobic and will continue to try to implement xenophobic policies, and the majority of people will keep voting against them.
This was widely understood to be a vote on how well the SVP can appeal to the center. Turns out pretty well but it's not entirely surprising given their recent election results.
So what will realistically happen, if we look at the trajectories of other countries, is that immigration will continue to rise, more people will be peaked by the discontent it can sow, and the popularity of this party will rise further.
I think this is sort of begging the question a bit, in the sense of assuming a specific conclusion is true when asking the question of whether it's true.
In particular, I don't think it's demonstrably true that immigration sows discontent. I do think that it can be shown based on the US example that far-right parties looking to sow discontent often scapegoat immigration as the cause for societal problems that may have nothing to do with immigration (like the classic "your cost of living has gone up coincidentally at the same time that corporate profits are at an all-time high and regulatory capture is widespread; it must be immigrants to blame for things being expensive!")
There are valid and reasonable reasons to dislike large-scale immigration beyond supporting despots for the sake of doing so. The mainstream parties are not offering alternatives, can you blame those who are disaffected by this rapid societal change from reaching out to support the first name that voices critique at policies they dislike?
It is not _the only reason_, but it is a big reason.
This part rings a little hollow when it's one of those mainstream parties that's doing the demagoguery.
>can you blame those who are disaffected by this rapid societal change from reaching out to support the first name that voices critique at policies they dislike?
Yes and no.
Can I blame people for recognizing that something in their life isn't working? No. Can I blame them for willfully accepting claims that offer no attempt at proving themselves with evidence, and that consist almost entirely of "people who look different than you are the only reason you have any problems"? Yes, because the average person shouldn't be so easily duped, and if they are, it's generally because they already wanted a reason to blame "those people" and anyone offering the faintest excuse ought not be "good enough".