dabac

That may well be the case.

That is pretty much entirely dependent on type and price range of MTB. An XC (Cross-Country) MTB with low-tread tires can be pretty decent on roads.
And if you're ready to throw a bit of money on it, finding one that's lighter than an average hybrid is no big deal.

IGHs and belt drives does have that advantage. Although the gap between belt vs chain in a good chaincase may not be that big. Look for drum or roller brakes if you really want to keep maintenance down. Depending on your own ability and the shops around you, belt drive bikes can be a pain to deal with when they finally do need an overhaul, or if you want to tweak the gearing a little. Chain drives can be serviced and customized "everywhere".

And remember that low maintenance still isn't no maintenance. No bike is immune to the consequences of extended periods of neglect.

There'd be a HUGE amount of personal opinion in that statement.
I might prefer a hybrid ahead of a drop bar bike if I was forced to ride in the drops all the time. Or perhaps if there's a lot of road buzz that can be cancelled out by the wider tires and lower pressures of the hybrid. Apart from that, I don't see any huge comfort gain from hybrids vs road bikes. Bike set-up is more important than bike type IMO.

All bikes I've ever ridden have held up to dropping off kerbs. Only issue I've had was when I tried to run 1" tires on a bike with panniers. Snakebite flats were a risk even at moderate loads. Unless your "jumping off kerbs" is a much more energetic thing than my "drop off kerbs", or you're a lot heavier, or run a loaded bike - particularly with narrow tires, you should be OK on pretty much any bike.

No idea what that means to you. But I've seen bikes described as "urban assault bikes". One of those might be a better choice if you're looking for a plaything, piece of sports equipment instead of a vehicle. And while quite robust, IGHs aren't an obvious choice is you're really into jumping.

The amount of fork maintenance required is closely related to fork type and how well you want it to work. Elastomer forks don't take much. Oil/spring can be quite rugged too. With low enough expectations, maintenance doesn't have to be much. Keep it lubed so it doesn't seize from rust and you should be good for years.