I knew you will look into it in detail but I will make some of the corrections and fill in the missing information. I agree there is a decline if you compare the current year with the 2015, 2016,2017 and 2018.God forbid somebody else do some research around here...
Ok deep dive it is.
Since you wouldn't name names I decided to stop being "lazy" and figure it out myself and my position remains unchanged.
With the exception of two fifth year players that I could find no info on, here is where everybody on UBC's current roster came from:
Jason Roberts – Unknown (Richmond)
Daniel Kaiser – Whitecaps
Jordan Haynes – Whitecaps
Sam Aiello – Mountain United (HPL)
Jackson Farmer – Whitecaps
Manraj Bains – Whitecaps
Mihai Hodut – Mountain United (HPL)
Ryan Arthur – Kwantlen Polytechnic (Transfer – Originally from Fusion FC HPL)
Victory Shumbusho – Whitecaps
Sean Einarsson – Whitecaps
Mackenzie Cole – Vancouver Island Wave (HPL)
Chris Fisher – Upper Island Riptide (non-HPL)
Kerman Pannu – Surrey United (HPL)
Logan Chung – Whitecaps
Sam Fletcher – Vancouver Island Wave (HPL)
Sebastian Dzikowski – Calgary Foothills
Riley Pang – Whitecaps
Mateo Donelly – Fusion FC (HPL)
Dallin Akune – Fusion FC (HPL)
James Graham – Winnipeg
Andrew Metcalfe – Seattle University (Transfer – Originally from Winnipeg)
Mitch Piraux – Whitecaps
Jora Saran – Surrey United (HPL)
Nick Fussell – Whitecaps
Thomas Gardner – Whitecaps
Rhett Freiter – Calgary Foothills
Luke Griffin – Unkown (Coquitlam)
Chad Bush – Duke University (Transfer – Originally from Ottawa)
Tariq Gareau - Oakville
Stefan Colbow – Mountain United (HPL 2017)
So on a 30 man roster there are 11 from the Whitecaps (residency, U23, USL, etc.) and 6 from other parts of Canada, plus 1 from a non-HPL youth club and 1 from another local University.
That leaves 8 straight out of HPL by my count.
9 if you count Colbow but he appears to have taken a year off before returning to school in which he played men's league for NorVan and, according to sources, he left the UBC program when he was told he would have to play for "Richmond" in Div. 1 with the rest of the reserves.
The two 5th year unknowns (Griffin and Roberts) I assume likely played HPL, but the league would have been in its infancy back then (launched in spring 2012 they would have graduated 2014 at the latest) so it is tough to say for certain as the landscape was different.
UBC lists 10 1st year players on their roster:
Only 2 from HPL (Aiello and Donelly). Neither dressed for a single game this season. As mentioned, I don't think Colbow is with the team, but regardless, he too did not dress for a single game this season.
So the ONLY two players that joined UBC from HPL last season (or three if you include Colbow) spent the entire season as red-shirts.
Maybe the kids will go on to have great UBC careers, but I think it is more likely that they bail on the program.
For the record the two Foothills products (Dzikowski and Frieter) were also complete red-shirts that didn't see the field. Fisher, Graham and Gareau got to play in the last game of the regular season plus got a trip to Nationals. Metcalf, GK, got the start in one regular season game against Victoria as well as in the loser game at Nationals. Chung, the Whitecaps Residency product, was a regular.
Those are the facts. Call it what you want, but I see it as a downturn in HPL recruiting. Again, all I can go off is what Mosher told me personally a couple years back which is that the local U18s were not able to cut it at his level. Take that for what it is worth.
Perhaps part of the motivation of having a VMSL team try and create more opportunity for local U18s to get experience with UBC and ultimately crack the roster. This has been mooted as one of the reasons that team perhaps would want to stay in Division 1 rather than go up to Premier, as it is a development squad.
Circling all the way back around to why did nobody at Fusion, etc. know about this tryout at UBC. Likely because if Mosher is only going to take enough HPL kids that you can count on one hand, he probably already has an idea who they are.
Does the fact that UBC is not taking a vast quantity of players from HPL (on the Men's side) make that league less valuable? That question is up for debate.
As we were then...
Here are corrections to your list.
Jason Roberts is HPL Fusion 2014 U18 team.
Luke Griffin is also 2014 U18 team of Coquitlam MF HPL.
Manraj Bains is SU U18 HPL. He also played U16 HPL for SU. He spent short time with whitecaps before he got cut. Also couple of players you listed as "Whitecaps" have spent less than year in the academy.
Sean Einarsson is not whitecaps when he came to UBC. He came from Surrey United. He played Whitecaps U23 in off season while on UBC team.
That will take your current year list of HPL players from 8 to 11 and will reduce the Whitecaps list from 11 to 9.
But I noticed is that HPL teams performance in the national championships is directly related to the UBC roster. If you look into 2014, 2015, 2016 HPL teams performance in the national championship it is easy to see why Moser was picking up those players.
Again you can make the statistics show what ever you want but I agree there is decline of HPL players in the current year because BC is not winning at U18 and now they switch to U17 national championship.