This microphonic is sum of many things. Normally it do not affect measurements at all. It may be problem in some heavyvibrating enviroment as example in wechile etc. And even if this is any kind of problem it is easy to solve using sevral methods. If it is problem on the table this effect is easy to minimize.
Why it is so microphonic.
Construction is so that BNC connector go directly axially to PCB and there very sensitive area.
This outer shield of BNC is directly soldered to PCB. Knoc it and all force and vibrations go to PCB and its direction is worst possible
If BNC is first fixed to some metal base and after then example side direction from PCB situation is perhaps more easy. (as example in Siglent, Rigol DS1000 and many others)
In very very early version BNC did not go at all directly to PCB. It was not microphonic.
If want that mechanic vibration do not affect this construction need be different. It can still construct to inside these scope dmensions but very different mechanic. Also front amplifiers layout on PCB can do different and isolate bending forces by cutting PCB around amplifier sensitive parts so that even if main PCB have some bending vibrations/waves they do not bend front end amplifier.
But all these need new design.
Also some componet need carefully select. (specially some capacitors in front end)
Now it can ask - is it forth of this price?
Do not knokc and hammer your scope when you do sensitive measurements and this modification of working practices do not cost anything. It is free.
If you want measure nail knocs pleasre also put BNC cover cap on it. (Real BNC metal cap)
It enclose BNC input so that external electric field can not affect to 1Mohm around 10pF very sensitive input) Put your finger near to open input and agen you have electrical phenomenon which may wonder.
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But If I want listen my water pump roller bearings I can connect nylon rod from bearing box shield to my scope BNC and "listen" with FFT these bearings condition ... (
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