
Not sure if this is a bug or intended, but personally I don’t think being able to equip one size smaller weapons with gimbals should even be an option.
The reason the Hornet is meta right now is because it can run things like S3 NDBs on S4 mounts. Weapon sizes should be fixed, and you should be choosing your ship based on the weapons you want to use. (Sabre and Defender only have 4x S3, though…)
Originally, downsizing through gimbals was meant to be a trade-off for the aiming assist. The weapon balance only really broke once ships were able to equip same-size weapons on gimbals.
I don’t think it should go back to how it used to be, where gimbals forced a size reduction, but overall weapon flexibility probably needs to be reduced.