Ultimately there’s no way to keep colors from tending towards white with the tonemapper. That seems to be what it’s for, more than anything else. By which I mean to say that it’s not exclusively for HDR displays, or possibly even essential for them.
What is strange is that green tends towards white as you’d expect, but blue tends too much towards purple, and red tends too much towards orange. You can add a little more green to your blues and a little more blue to your reds and it will look much better. Could be an error with the Linear color>>ACES conversion.
If a colour is causing bloom, it’s already bright. It won’t look flat and dull compared to sparks because they’re relying on the same data for brightness. If anything, SDR is underrepresenting just how bright these things should appear. E.g. That mushroom in the OP would look as bright as the sun in HDR. After ACES, the only change its that it’s now white instead of orange.