Kpt, can probably answer better.
IIRC, the 10x Zoom was introduced:
Firstly due to the limited optical processes of SH3, i.e It's not the MkI Eye Ball.
Secondly, with the introduction of the Grey Contacts mod, meaning that players must now identify targets by checking the flags, it was decided that 10x was a 'tradeoff' for this added realism. To compensate, I think the only the UZO & Attack Scope goes to 10x, IIRC the Obs scope is unchanged.
Again, it comes down to the fact that we're not actually looking through a real scope.
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