My DH is Polish, but we live in Ireland, so our experiences will be different but perhaps similar.
About 60% of our friends have left in the last two years, with maybe half of those still here making plans to go. Most have been here since 2004/2005. A lot have been/were building homes in Poland while working here, others brought in their home cities and have been paying off the mortgage quickly. A few are leaving mortgage free, two have freehold homes and investment properties. The economy in Poland has been improving while living costs in Ireland have risen considerably - much like the U.K. Coupled with the increase in airfares (no more €5 flights), the homesickness etc, I’m sad but not surprised that they’re leaving. Those who have learned English well are particularly desirable in the Polish employment market.
I do sometimes hear xenophobic comments including colleagues who don’t know of my DH, but I get the same occasionally about myself (my time abroad means I can pigeonholed as Australian or English).
My DH has extended family in Yorkshire (Barnsley and Wakefield), and in Portsmouth. Yes, some have had enough but Brexit isn’t the only factor, just part of it. He also has family in Netherlands and Germany (as do I), they’re staying put but are more worried about their safety in Germany due to the asylum seekers. In my limited experience from regular visits to Poland, they can sometimes be unwelcoming to people of colour. As an example, a cousin married to a guy from Mauritius was banned from being the godmother to her nephew; she and her sister are orphans, so the Church’s ban was very upsetting to her. Equally I’ve sat in surburban Wrocław or Krakow often late at night for a tram or bus playing with my phone, and not had any bother. I couldn’t say the same about Manchester or London. I’m white though.
There are a section of DHs friends who haven’t learned English while here, and they’ve struggled more to build a nest egg. Sadly they are more likely to stay in Ireland as the social supports can be better.
Indians in Ireland; if you complete an a Undergraduate or Masters degree, you get a two year grad visa. At the end of two years, if you earn the required minimum (€38k AFAIK) and have a permanent job, you get a five year visa leading to residency. The local Irish universities are churning out Indian graduates, so they don’t need to recruit staff directly from India. Also INIS are getting tougher on marriages between EE and non EU couples, so that loophole is fading.