It depends where you go and how it's managed by Governments. Some are very conscious of keeping touristy areas tidy others not. (Mainland Europe)

In the UK there's been a lot of change imo. It's often concentrated in certain towns and cities. I used to visit Birmingham as a youngster as I had friends studying there and it's changed a lot. Working in London recently for 6 months it's changed a lot.

I have been trying to figure out why successive Governments have encouraged mass migration when the majority do not want it (Brexit). My research suggests it's demographics and keeping the lights on in terms of taxation, national insurance, and paying for liabilities such as massive pension obligations, NHS and benefits. (UK State pension £3.5trn unfunded, public sector pensions £1.5trn unfunded)

The OBR suggests the UK needs 350k people net per annum, even though it appears it's a failed strategy and a short term fix.

Immigrants will also age and evidence suggests they also become a liability in thelong term as fertility rates fall and cost a lot more than pay in tax and NI. (Not the case for highly skilled workers)

So now we have the Reform Party leading in the polls @ 35% and Labour at 14% Conservatives at 14%