You seem to be thinking of the 660p. I don't believe the refreshed 665p was ever priced that well, as it came at a time when SSD prices were climbing back up a bit. Looking at the price tracking data on PCPartPicker, the 665p never saw a sale price below $110 since it came out a little over 8 months ago. Typically, it has been priced in the $130-$140 range at Newegg, with sale prices sometimes bringing it down to $110-$120, and even less attractive pricing at other retailers. So, significantly higher pricing than the 660p was regularly seeing last summer. And at those prices, there have been similar, or in some cases better drives available from other manufacturers, so it never became to go-to budget option that the 660p had been for much of last year. And this year, the original 660p hasn't really been priced much lower either.
As for performance, the 665p was configured to make a larger portion of the drive available as cache at any fill capacity, and didn't slow down quite as much when that cache was filled, so it was arguably worth a 10% or so premium over the 660p. Unfortunately, it was priced a bit too high at launch, and never really came down enough to make it stand out above the competition.
At the very least, it seems likely that Intel will have a new drive to fill its place, and with any luck that drive might see better pricing and features, so its discontinuation might be a good thing.