Peak power, yes, the cars will have a thousand horsepower. On average, though, because of the conservation of energy and fuel flow limits. They will have an average power output of less than 600 horsepower, closer to 530 if I recall correctly. Enineering Explained made a good video about it. So overall I think saying the 2026 cars will also have 1000 hp is sort of misleading since it will only have that power available for very short amounts of time.
It depends. They have go limit the power of the cars somehow, and fuel flow limit is i think a good way to do that, because it promotes efficiency. Things like taking away electric energy recovery from the turbo seems stupid in contrast because it removes efficiency
A lot of people don't realize a major objective of technical regulations is to intentionally slow the cars down and keep them below a particular speed.
I'll be surprised if these cars get over 250 km/h at their fastest. Then again, I don't have access to their testing data, so take that with an ocean of salt.
They still have access to 1000 BHP for short periods, while weighing less and having less downforce that will almost certainly result in less drag for most cars. I would not expect peak speed to be that much slower than now, just average speed over the lap.
Sure the drop to 6 gears from 8 (if it goes ahead) is going to hurt but not being able to use all 1000 BHP on the straight at somewhere like Monza means you'll just be a sitting duck all day long, RB have shown that when they had their biggest DRS advantage.