UK potentially leaving the EU?

Yes.
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Not because the UK will leave the EU - I can't see that happening, and even if it does, it will not affect your ability to live and work wherever you might like in the EU, as the UK will still be part of the EEA, and probably EFTA.
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But because you obviously live here, obviously care, and therefore should be voting in national and regional elections, and you can't do that unless you are Belgian.
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Another good reason is the extortionately expensive British passport. You'll be able to travel around the EU/EEA quite happily on a Belgian ID card.