Surely you would want something that actually IS testing software, not just a fixed grep expression.
Depends on the testing being done. If the goal is automation testing then we probably must have it (sometimes you can remote control), if the goal is manual testing then NO. If at all possible all you want on the machine is the the software to be tested and what it absolutely MUST have to run (target OS, 3rd party software it’s supposed to interact with) and absolutely nothing else, as any other software could be throwing DLLs or such around the skew the results.
Which spins right back into why they use these cells for testing, remove all variables that could skew things.