Something a lot of people, and even high profile talking heads, don't account for is that expiring contracts only have trade value (for the team possessing them) if they're willing to take on long term money.
Could we have gotten something of value for Chandler or Rivers? Yeah, probably... but that "value" would have also come with a year to year contract rate similar to what those guys were making. So, if that contract rate carries beyond this season, then that player or players need to be move valuable than the massive cap space dumping them or letting them expire would yield.
I have no clue if we'll land anything of significance with the gobs of cap space we are projected to have... but I think I'd rather that space than the disposable, overpaid, flotsam that other clubs would have been looking to eject (along with a really late first if we're lucky).