Perhaps - I spent most of my time amongst the Muslim community in London.
But I travelled to Dewsbury in about 1981/2 to join Tableeghis there and went to Leeds and spent 2 weeks there. There was definitely a rise in Islamic consciousness.
It started with the Islamic revolution in Iran in 1979 and continued with the Russian invasion of Afghanistan and the subsequent rise in western Jihadis that began in the early 80s.
So personally I would say it was UK wide - not just London.
Your estimate of mid 90s seems terribly late to me.
My hey day of Islamic fevour was the early 80s.
By the mid 90s I was having serious doubts and already missing occasional prayers