Well I believe that we (the users) have set up the conditions for that to be as it is. High OD is all over (but honestly I can't blame anyone training it high as it is a super skill). And high JS as well. LI is also all around. So high pressure = end of the clock 3p shots as a result from very high JS. I guess you know how that ends. Pretty much like your example.
And JR is actuqlly not that expensive on its own. But just as SB is expensive in combination with all other inside skills already high this is also true for JR with the other three skills in the SG formula that add to salary.
The problem is arguably less that JR is expensive and more that OD is very expensive when you get into the SG formula. On Buzzer-Manager, for example, take two guys:
PG: all 7s except 20 passing == 26658 salary
SG: all 7s except 20 JR == 20964 salary
now if you put each of their OD to 20:
PG: 66161 salary
SG: 92131 salary
And of course, a similar (but even more pronounced) differential occurs with JS.
So if you want an outside scorer, the JS+JR+OD all have heavy effects on the salary in the SG formula. And given the amount of OD currently in the game, it's a massive challenge to try to find some way to create players who can score offensively and still be effective defensively at all, let alone trying to do so at anything approaching the low salaries available to the LI-built PGs.