I preface this by saying the lack of multiple upper tier offers for Jamal isn't due 100% to lack of exposure, but it certainly is a legitimate factor. That being said, coaches did have the opportunity to see him in EYBL, but not for 16 games. Only 2 EYBL weekends were of the live evaluation variety. He broke out on the scene in New York where nobody had ever heard of him prior to that, so unless a coach was intending to watch the opposition, they simply weren't watching The Family because they had nobody of note that would compel legit high major interest. After EYBL Indiana (the 2nd live evaluation period), he received offers from UM, Marquette, Florida State, Boston College.......certainly a nice haul for someone that was literally unknown to anyone outside of Michigan prior to that.
Peach Jam is where the highest concentration of HM coaches were located in early July, followed by Vegas in late July. Jamal did not play in the Peach Jam, and played in Orlando during the late July period rather than Vegas. Literally 85-90% of all shoe circuit teams (Nike, Adidas, UA) were in Vegas during the late July period playing vs one another. That would've been a golden opportunity for him to showcase himself in front of HM coaches.
In terms of Matthews, sure it impacts his ability to contribute at Michigan. But where I disagree is that Poole being at La Lu will somehow give him an upper hand over Jamal in college. Jordan already played vs higher level comp the prior year with Wisconsin PGE, so he had a year's experience prior to running with Mac Irvin this summer. And being frank, Jamal outplayed Jordan by an extremely wide margin in every facet of the game during EYBL this year. And that occurred with literally no experience vs. top flight competition on Cain's behalf prior to this spring/summer. It's not hard to see that Cain's potential is considerably higher than Poole. I love Jordan Poole's game, but my eyes saw what they saw, and the stats reflect the same. Bottom line for me, is that when both faced elite competition, Cain outperformed Poole considerably despite having a year's advantage in terms of experience. With proper strength, conditioning, and development, definitely think Jamal can push Poole for playing time as a sophomore if not earlier.