That effect is clearly illustrated here (ignore the unrelated colour fringing on the text – that is a GIF artefact):
The “blue highlight fix” LMT is not really intended to counter the hue skews at high exposure, but rather the very harsh artefacts resulting from values which are outside the AP1 gamut. Because you are starting with an sRGB colour, it is well within AP1, so that LMT is not really an appropriate fix.
I would suggest that rather than starting out by thinking about sRGB source colours, you choose colours which give the result you want when viewed through an ACES output transform. So don’t necessarily start with sRGB(0, 0, 1) if you want a saturated blue. Choose a colour which may be outside the sRGB gamut (but in AP1) which gives the result you are after. As as example, here is a colour which starts blue at normal exposure, but goes through a more cyan tint as it goes into over-exposure. Is it “right”? The answer to that is subjective. But it may be more the sort of thing you are looking for aesthetically (bearing in mind that sRGB is not capable of displaying a colour which is both bright and blue).
