Yeah, I've watched it all happen, being there nearly every year since the mid-1990's. But the trouble is, I'm in a different country each year, and while some of the changes are common to most, it's not all universal.
We have only spent a great deal of time in Ireland and the Netherlands with a week or so in Scotland which was on a boat visiting smaller port towns with only a short time in Glasgow.
One of the expressions, and law, they have in some/many European countries is "anti-social behavior." It really fits so many problems. We did not really see many/any issues in our travels in Scotland and Ireland, other than beggars. In Dublin we did see way too many homeless people but Ireland has had a homeless problem since Cromwell's visit. Having said that, they should have fixed the problem decades ago but have only made it worse. We talked to an American living in Ireland who told us how time consuming it was to do a small addition to his kitchen. It really was horrible, and as I have read since then, part of the problem.
There have been court cases, where people have built homes on their own land, without planning permission, because they were HOMELESS. They could not get planning permission to build on their land, even being homeless. They built anyway, were taken to court and threatened with prison if they did not tear down their home. Tearing down the home will make them homeless again. That state has no housing available for them at all..... You can't make this up. It is right out of Orwell.
BUT, the government has plenty of housing available for the horde, of military aged men arriving illegally. Native Irish, forget about it. There are been too many cases made public of Irish people being kicked out of housing to be replaced by the newly arrived. The government pays more for housing for newly arrived, aka, the illegals, than they do for their own people. It is unreal.
In the Netherlands, we have seen quite a bit of "antisocial behavior" on the trains and buses. It was not from the Dutch but from the newly arrived and very obvious. We were taking a train from the airport to where we were staying and I was in the area where one can keep a bike, luggage, stroller, etc. An older Dutch dude got on the train, and seeing the luggage, asked if I was moving to the NL. I said no, just visiting. You could tell he was not happy with all of the people moving to the country. On our first visit, we were waiting to go on a tour of a building and an older Dutch couple was waiting as well, and started a conversation about the newly arrived. An interesting conversation but I sure was not starting it.

The Dutch have this thing were they keep blinds open most of the time, even at night. Kinda odd to be honest but it is their culture. One does NOT walk by a home and stare inside, which is obviously rude, but the newly arrived do look. And it is not just a glance either. It is spying. We saw this in the last house we rented. The Dutch did not do this. We noticed that the newly arrived are not following Dutch cultural norms, even the few we know about, and this is really anti social.
We had similar conversations started by our "neighbors" in the NL I really wish we could have talked to them more.
In Ireland there will be violence. It has already started at a low level because the government is not enforcing the law equally and blatantly ignoring what is happening. What is scary, and very Orwellian, is how the government and media are hiding what is happening. It is like they are following 1984. There have been incidents across the island from groups that are usually, historically at odds with each other, against a common problem. The irony, is that the Irish and UK governments have created a situation which might cause the splitting of the UK and the joining of Northern Ireland and Ireland. The Good Friday Agreement has the process defined but the will most certainly has not been there at all. I did say might, and quite a bit would have to happen, but events are happening. It really is unreal what is going on over there. The UK has a political way out of the this mess, and the political solution has started, even with the current government canceling local elections. Ireland is the bigger problem/danger because NONE of the political parties are against what is happening even though the vast majority of the Irish do not like what is happening. When a people don't have a political solution...