Who still needs decibels?

[ilayn]

This is already dropped in accordance with Astrom, Murray for a very good reason. See for example python-control/python-control#46

A step further than this is not using decibels at all since we don't have any matlab legacy. Plus, currently the plots are logarithmic but the tooltips are in absolute. Hence visually it has the log flavor but the value can be read properly without using a strange interim unit. That makes one less dropdown menu around the plots. But I am open for counter-arguments.

[ilayn]

decibel use is dropped but available as extra arguments.

Consider stopping decibel in your work unless you have to explicitly require it. It is just silly multiplying a perfectly log axis with 20 and confusing everyone just because of old habits.