Why are Cubemaps and Specular highlights not equally blurry at the same Roughness / Glossyness value with standard pbr shader?

So I use the standard shader that comes with unity and I cant quite shake that feeling that something is way off with the blurriness/sharpness of specular highlights vs the cubemap reflection. In order to make sure its not any of my textures that are authored incorrectly I did a little experiment:

• Made a sphere and gave it a default shader with all white albedo -cranked up the smoothness/roughness/glossyness slider to the max ( that actually makes the specular highlight become so sharp and small that it disappears so I took it down to 0.97) -cranked up the reflection probe resolution to the max (that is 2048 although I cant really see a difference past 256 ) -place a point light near it with a color value of pure white and intensity 1

and sure enough the sharpness of cubemap and specular highlight are way different:

The cubemap displays its highest resolution mip stage with no blurring at smoothness 1 and the lowest (most blurred) at 0 as far as my eyes can tell so far so good but that specular highlight is always way too sharp the look it has at 0.5 is the one I would expect or "find aesthetically pleasing" at 0.9

Of course I understand that a point-light source and its specular highlight are abstract "none-real-life" concepts so there is no real comparison one could make via photos etc... but usually people use point-lights for stuff like light-bulbs torches and other small light-sources that emit photons in all directions. and if I check out those in reflections on photos or in real-life they match the sharpness of all the other reflected things.

Example image of a wet street

So Question: can I access and tinker with the source code of the default shader and add my own tweak/bias/fudge factor to align the specular highlight blurriness to the cubemap ?