To be fair, Carter did measure with a longer wingspan than Ellis (6’8.75” vs. 6’8.5”) so let’s not pretend like “length” is only defined by standing reach.
It’s also worth noting that Carter’s vertical was much better than what Ellis posted which I think is a complementary data point to consider when looking at standing reach.
For example, Carter measured with a 8’2” standing reach, 35” standing vertical, and 42” max vertical. That means at a standstill, Carter’s hand can get up to 11’1” to contest a shot, and with a running start, Carter’s hand can get up to 11’8” to contest a shot.
Now let’s consider Keon who measured with a 8’6” standing reach, 28” standing vertical, and 35.5” max vertical. That means at a standstill, Keon’s hand can get up to 10’10” to contest a shot, and with a running start, Keon’s hand can get up to 11’5.5”.
As you can see, Carter can technically contest shots at a higher point than Ellis which helps negate the difference in standing reach while at the same time having a longer wingspan which is more important for deflections, playing the passing lanes, stripping players, disrupting ball handlers, etc.
Then you add to the fact that Carter has been an excellent rebounder for his position in college and will likely be a better rebounder than Ellis and it makes his shorter height/standing reach) less of an issue.
Then you add to the fact that Carter weighed in 26 lbs heavier than Ellis and it helps negate that height that much more as it allows him to bang with stronger players without being moved off of his spot.
But despite Carter having 26 lbs on Ellis, his agility/quickness/speed tests were better as well:
Lane Agility
Devin Carter = 10.63 sec
Keon Ellis = 10.87 sec
Shuttle Run
Devin Carter = 2.90 sec
Keon Ellis = 3.02 sec
3/4 Sprint
Devin Carter = 2.87 sec
Keon Ellis = 3.18 sec
So what do we potentially have in Carter? A defender who is quicker, faster, and stronger than Ellis who technically can contest shots at a higher point in the air than Ellis and will very likely be a better rebounder than Ellis. Now does that mean that Carter will be the better player or defender? Of course not. But I wouldn’t be surprised (and that’s coming from a guy that loves Ellis).