I'd disagree mildly. I remember that around the time the UK actually left the EU, a newspaper in Dubai (strongly against Brexit) interviewed a group of British expats. Out of the responses, only a quarter were mildly against Brexit while the rest were actively in favor of it. The numbers were even further skewed if I were to incorporate personal conversations.

In general, I've found Brits outside the UK in touristy/retiree expat hotbeds like Spain, Portugal or Dubai to be extremely in favor of Brexit, and mostly racist. Britons in the Isles or in other countries tend to be really friendly and open minded. This could be a reflection of the kind of expats who move to places - older expats might choose sunny places like Spain or Dubai while younger expats might prefer to settle down in the US or Germany, where there are better career opportunities.