"A team of researchers from British universities has trained a deep learning model that can steal data from keyboard keystrokes recorded using a microphone with an accuracy of 95%."

https://www.bleepingcomputer.com/news/security/new-acoustic-attack-steals-data-from-keystrokes-with-95-percent-accuracy/

stuff like this is why if you worry about high level targeted attacks, secureboot is not sufficient to protect against physical attacks.
cameras, microphones and other data extraction tools (e.g. SURLYSPAWN, COTTONMOUTH, FIREWALK) are easier to install and hide than touching the actual device itself.
the only effective protection would be to physically improve the devices location like no visual like windows and surveillance to spot intruders.