They make leather bike suits with airbags inside them. In a crash, they inflate before the rider hits the ground. Absolute genius bit of kit.
Imo, motorbikes are not intrinsically dangerous, but a safe rider needs far more alertness, better peripheral vision, better reading of the road etc than all but the very best car drivers.
The late Mr Lakie rode bikes regularly for 44 years, including a few years as a bike courier and spells where he was doing a 50 mile motorway commute daily. Apart from a couple of spills when he was learning, he only had one accident, when a car pulled out as he was passing it, and never had another in his remaining 40 years. His brother, who used to race a bit and do track days, has a similar safety record.
If your DH isn't a twat, is a skilled and alert driver, is prepared to do a Bikesafe or similar course, and the money isn't an issue (bikes and all the gear are expensive), I wouldn't try and stop him. But if he's like my friend's DH, who got done for doing 130 in a 70 on a notoriously dangerous stretch of dual carriageway, then he's clearly not cut out for being a decent motorcyclist and shouldn't even think about it.