As a general rule lately, every year F1 gets slower
That's not
exactly true. Sure, the FIA keeps doing their best to slow them down, but the teams keep finding ways of preventing them from actually slowing down.
In the 2010 Australian GP, for example, Vettel qualified on pole with a lap of 1:23.919. The fastest lap ever set during a race on that circuit is Schumacher's 1:24.125 back in 2004, for which race he qualified on pole with a 1:24.408. The 2010 race was wet, which is why the 2010 race laps were several seconds slower, but Vettel's qualifying lap was faster than Schumacher's official record lap there.
Pulling another random example, Vettel qualified for the 2010 German GP with a pole-winning lap of 1:13.791 and the fastest lap of the race was 1:15.824, also set by Vettel. The fastest lap ever recorded during a race at Hockenheimring is Kimi Räikkönen's 1:13.780 set again in 2004, which is only a hundredth of a second faster than Vettel's qualifying lap and only 2.1 seconds faster than the fastest lap of the 2010 race, which is still faster but only barely. Getting within two seconds is pretty decent considering the FIA has spent six subsequent years trying to slow them down since that fastest lap in 2004.
Unfortunately, this may change once we get to the 1.6 litre four-cynlinder engines rev-limited to just 12,000 RPM (down quite a bit from the current 2.4 litre V8s limited to just 18,000 RPM) in 2013.