Hurt the Bruins in the short-term I think but it's beneficial in the long run, at least financially, which is any owner's top priority. More teams and a more competitive league means more money to be made from broadcast rights, sponsors etc. And a bigger pie means every stakeholder gets a larger slice. It's shrewd business.
In the end, it doesn't seem to have altered much for the Bruins' on-ice performance, at least not yet. They were a nearly-but-not-quite team through many many years in the 20th Century, and they're still that in the modern cap era. The more things change.....
I think that Jacobs was outvoted on some issues, and was not prepared for the outcome. He anticipated what the outcome was going to be (CBA), and no reasonable person would have bet so much of their roster based on such assumptions.
For example, he assumed that the market would be flooded with UFAs, but with some teams against the cap. Then, the owners voted to allow amnesty buyouts. All of a sudden, competition for those UFAs became more intense, driving up prices.
That caused him to horribly miscalculate, signing virtually none of his UFAs before the lockout.
OTOH, he may have been in favor of tolling the contracts, to add more UFAs, but that really hurt the team, b/c it cost them Goncher, for whom they had just paid a huge cost from the Caps.