I know both these places well, and yes they have gone downhill. Is this due to the influx of the Asian community? Remember, correlation is not the same as causation.
Let me put it this way the Alum Rock 40 years ago it was a VERY nice place
no dirty streets,no carp everwhere, you used to see people cleaning the font door steps with polish.
UB40 and The Specials used to go to the pubs there not so long back.
It was clean and tidy. So make your own mind up what changed in them years.