Most normal users don't know what dB means so presenting a dB scale slider as 0-100 is easier to understand and still works in terms of perceived volume.
I quite agree with this, and this is also precisely why I think Construct should also do the translation between dbs and 0-1 for the user, because the Construct user currently cannot just input 0-100 or 0-1.
Rather than having the average Construct user look up how db works, the relationships between volume, loudness, and power, figuring out that negative infinity can be used the lowest volume instead of a hardcoded "mute" level, stepping dbs by 3 or 10 × log₁₀(V2/V1) to double "loudness" ect., trying to understand articles like (https://www.dr-lex.be/info-stuff/volumecontrols.html) and (https://dcordero.me/posts/logarithmic_volume_control.html), reading through the wikipedia page on psychoacoustics and not understanding a single word, ect...
According to the latter article, "implementing a volume control logarithmically is actually a quite easy task", which I'm assuming is a similar to the point of view from Ashley, but I'm pretty sure the vast majority of the users here are not going to understand the "simple extension" example also in that article besides the fact that it doesn't directly apply to Construct, nor how to implement that in Construct.
Even if the user is given the approximation formulas like volume^4 or 33*log10(volume/100) where volume is a value between 0-1, I still get the feeling most probably still wouldn't be able to apply that knowledge to their own projects themselves...