The man organising this planned march/protest has already made himself notorious on several previous media outings. He is clever, and knows that this plan will provoke hostile responses. He will thereafter be able to point to those responses as evidence of anti-Islamic sentiment.
So to oppose him vociferously is to play into his hands.
Unsurprisingly, some of his most vigorous critics are other British Muslims, wno are only too aware that his main aim is to ensure the prolongation of animosity.