At the time Ainge made that comment, Webber had already disgruntled (can I use that as a verb) his way out of his first team, got injured in 95-96 and played only 15 games, and was two years away from moving on again to a third team. Meanwhile, Penny along with Shaq had just made a finals and an ECF, predictably since Shaq was such a monster.
Knowing what we know now with Penny's knees not being able to hold up and Webber eventually settling down and being the best player on some great Sacramento teams, the trade doesn't seem as one-sided as it did early on in their careers.
How does it relate to today? Well I don't see a Penny in this draft, nor is Fultz as high-profile a prospect as Webber was back then. Webber was pretty much destined for stardom and he had size, which was what every GM prized first and foremost at the time, though Webber's game would actually fit today's game even more. In that sense, if a Webber came out today I could see a team maybe not offering 4 picks but probably 2-3.
If you want to compare Webber's value at the time of the draft to more recent top picks, I'd say he was on a level around Durant/Oden but below Duncan and James. I'd put him slightly above Towns and Davis and a tier above Griffin/Howard.
Anyway, almost every team would have kept the pick and taken Webber in that situation. It's really only because the Magic were the only team that already had Shaq that such a rare trade like that happened.