That is the problem with your statement. No we did not get a first round pick. Not any more than my neighbor can sell me his "brand new car" that has been sitting in his driveway for awhile.
Yes it was new once. It isn't new now. Keon isn't a first round pick today. In fact history has shown that FORMER first round picks traded during the first year of their rookie contract are routinely worth very little if anything. Teams don't trade away a high upside valuable first round pick after seeing them every day for months if there is amazing untapped upside.
They trade them when they realize there is little upside and other franchises haven't caught on to the stink yet.
A first round pick has way more value than Keon.
Not to say Keon has no value, with the lack of talent on our squad he probably is the most talented young player after Simons/NAS. But his value is way less than the 21st pick value back at the draft, or a future first round pick.