We've previously had and currently have reactive dogs (a term I prefer to "fear aggressive").
With our current reactive dog, we've spent the best part of two years in solid work to ensure he can now walk nicely on lead past other on lead dogs - that's been huge progress for him.
However, wherever it's possible on walks, I still make sure he's given plenty of space, and this often involves taking avoiding action when other dog owners approach.
Many dogs need space for many reasons - bitch on heat, recovering from illness or operation, new rescue dog, dog in training, reactive, elderly, blind, deaf etc...
If you see a dog owner taking avoiding action, please respect this and don't be the "He's only being friendly" owner whose off lead dog goes bounding over, kicks off WW3 and then gets offended at a less than warm reception.