I think saying vehicles are softer/harder is an over simplification. I think it is helpful to split them into transports and gun platforms and think about how well they do the roles they are intended for.
Transports have taken a big hit. It is harder to stop them getting there as stunned is less likely, but everyone could buy an upgrade to avoid this if needed, so all this does is makes them a bit cheaper, if this is important to you. Marginal at best. BUT it is easier to kill them on the way there with glancing, and at close range a quick melta to finish them off by taking the last hull point... and if that does not work there is the 3+ to hit assault. Smoke is less good too and you can't get out after moving as much as you used to (only a small hit). The loss of the ability to assault out of them makes them much worse too.
Gun platforms, on the other hand are now better. Either they have rubbish armour (like vypers) so the rules have not really made them much easiler to kill (it is hard to get worse than "likely to die from the first shot"), or much heavier armour (e.g. predators) so they are less vulnerable to multishot glancing weapons and so are not really easier to kill either (ok there is a third class of skimmer gunships, like the Falcon, but the jink save is not a bad trade off for hull points). However, they can now keep shooting no matter what and weapon destroyed does not automatically take out the best one. They can also shoot more guns and move and their blasts are better. Their longer range keeps them out of range of melta and rapid fire plasma. Yes, the will probably die quicker than before if someone puts concentrated firepower into them, but they will be more useful before they do, which seems like a good trade off to me. Most games my Falcons only fired 2-3 times in 5th, even if they now die on turn 3, I probably have had more shots out of them.