I'm trying to improve my Spin&Go/HUSNG game and I've ran in to another question, this time about 3betting all-in.

My question is: why would one decide to 3b ai with a more linear range, instead of a polarized one, when all 3 options are still available (fold, call, 3b). Because as it seems when I run some ranges trough equilab is that when it comes to range vs range, in equity is doesn't matter too much which range you'd jam with (examples below, please feel free to correct on the ranges I've used).

Yet if we would opt to 3bai with a more linear range, our flatting range pre would definitely become more weak. Or is it that when effective stacks get more shallow, relative hand value goes up so the strength of our calling-range sort of stays the same because we can stack off more light?

Note: I've left out JJ-AA in the 3bai ranges as I believe most Villains wouldn't always jam these type of hands in Spins/HUSNG at say 15bb effective.

And actually my biggest concern is: is my thinking just way off here and am I missing something very obvious?

Linear comparison (HERO = BU):

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Equity Win Tie
BU 55.88% 53.51% 2.37% { 77+, A7s+, K9s+, QTs+, A8o+, KJo+ }
SB 44.12% 41.75% 2.37% { TT-22, A4s+, K9s+, Q9s+, J8s+, T8s+, 98s, A7o+, KJo+, QJo }
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Polarized comparison (HERO = BU):

Equity Win Ti
BU 56.32% 54.05% 2.27% { 77+, A7s+, K9s+, QTs+, A8o+, KJo+ }
SB 43.68% 41.40% 2.27% { 99-22, A2s+, J7s-J5s, 97s, 85s+, 75s+, 65s, A7o+, KTo }
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