This isn't a major concern. He's clearly a very good coach and has done well at BYU. My one concern is winning in the post season.

Here are Coach Pope's post season's since becoming a head coach.
UVU 2017: Overall record (17-17) Conference tournament (1-1). CBI Semifinals. (2-1)
UVU 2018: Overall record (23-11) Conference tournament (1-1) CBI Quaterfinals (1-1)
UVU 2019: (25-10) Conference tournament (1-1) CBI Quarterfinals (1-1)

BYU 2020: (24-8) Conference tournamet (0-1) (loss to SMC) March Madness cancelled.
BYU 2021: (20-7) Conference tournament (1-1) (loss to the zags) March Madness (0-1)
BYU 2022: (24-11) Conference tournament (1-1 (loss to USF) NIT (2-1)
BYU 2023: (19-15) Conference tournament (2-1) (loss to SMC) No post season tournament

BYU 2024 (23-10) Conference tournament (1-1)

You can see at UVU that the team gets better in the regular season over three years, but isn't able to capitalize in the post season. Pope has almost always had a good regular season in the WCC but isn't able to beat good teams in the WCC tournament. He went 0-3 against the zags and SMC in the post season.

I'd be interested to hear what CB thinks is the reason behind this. Or even if there is a trend at all.

I believe this is due to lack of adjustments made in the post season. It seems like Pope carries over all his same sets and schemes from the regular season without adding new wrinkles or change ups. I'm not asking him to write a whole new playbook, but just make adjustments to current plays to throw off the opponent. Your opponent has a full season worth of film study on you, and should know every "go to" play you have. BYU just needs a couple wrinkles in the plays to throw off the other teams' defensive plan.

That being said, Pope has done an amazing job at BYU and I sincerely hope he remains at BYU for his entire coaching career. BYU has a great opportunity this year to Buck this trend. None of Pope's team have been prepared for March Madness like this current team. Go Cougs!