You are right, but the ones i have worked in, in the north west, mostly still had the tanks in place, but empty.
The cost of re decorating grants, the extra work involved in reomving the tanks, often led to them just being capped off and left in the loft.
Not all of them get updated. I visit a house where you still pull the chain when you use the loo (toilet.)
I'm not saying that is in every case, just that I have seen several in the past few years like this.
As for the firewalls, there was a big push to block these a while back, one because of security, easy access to other houses, and two, because of the fire risk, not many councils would want to be seen to be at fault if a fire broke out and spread because of a lack of firewall.