The ability for drivers to turn up the turbo boost pressure was also a factor; Piquet was fond of that on starts, as he did it at Osterrichring in 1987 (which worked great until half the field shunted into each other). Of course, the drivers also had a picky fuel limit, so they couldn't run it all day long.
Boost pressure was limited to 4.0 bar in 1987, and further reduced to 2.5 in 1988. Most race lap records were broken in 1987, though qualifying times were down a bit. I don't think a single lap record fell in 1988, because most engines made like 150-200hp less, or they'd jumped to the 3.0L NA engines. While there was a push to rid the turbos around mid-1986 for '89 as per the Concorde Agreement, there was also the matter of re-designing the front "axle" centerline of the cars for 1988.
All-new chassis designs required that the pedals may not extend past the centerline when pushed down, to protect their feet. But the caveat was that if you kept the '87 design, you could get around those rules. So Ferrari ran their F187/88 model, Arrows ran their old car, and so did Zakspeed. (Osella famously debuted a "new" car to the wrong old specs, but renaming their engine meant it had to be treated as an all-new engine and got disqualified...So Osella!) Back in those days, it wasn't unusual for teams to introduce their all-new car after a few races, or just modify their old car to newer specs, and fly it down to Brazil for the first race.
Teams couldn't couldn't use an old car around a new engine, so that's a big reason that McLaren was so dominant in 1988. Literally nobody else was competing with a new car and also had a 100 horsepower on the rest of the field (save Ferrari).
Of course, I'm an old fart, don't even try to understand why people are willing to put on such hideous outfits or even pay for it 
