Why would this be good for the game?
As it stands, the detonate function is an "instant win button." All cyborgs in the round can be very quickly destroyed regardless of their location from the comfort of a single console. This is highly frustrating for the cyborgs involved, and it's a very cheap, thoughtless experience for the person doing the detonating.
Detonation can happen to both subverted and non-subverted cyborgs alike, and is capable of permanently removing them from the round by destroying the cyborg's brain.
In most cases, the ability to lock cyborgs makes the detonation function completely redundant. Locking a cyborg allows them to be taken to robotics and de-subverted so they can continue a round.
Removing the detonation feature increases the quantity of fun that can be had in a round.
Scenarios:
For a normal, unsubverted cyborg, an antagonist may choose to remove any cyborgs they may see as a problem once they have gained proper access. Brains will be left on the floor, sometimes in out-of-the-way places. If they never received MMI radio upgrades, they may be trapped in this state for a very long period of time. This is not fun.
For an emagged cyborg, whoever gets to the console to take care of the cyborg problem simply needs to lock them to remove the threat they pose. However, they may also chose to detonate the cyborg without any repercussions. The latter option permanently removes that cyborg from the round and is unnecessary. Also it leaves a giant hole in the station hull and may harm bystanders.
In the case of a malfunctioning AI (the scenario where the detonation feature seems to make the most sense), the AI is both empowered to and extremely incentivised to completely destroy RnD to prevent use of a robotics console, and is essentially a requirement for a successful Malf AI. Unless the AI does not know what they are doing, they will nullify the console's use anyway.
A Hypothetical Rhetorical Comparison:
Suppose that all members of the crew also had bombs implanted inside them, and a special console allowed these bombs to be detonated at any time without physically seeing the person you are destroying even once.
How engaging would it be if all the antagonists in the crew could simply be deleted at the push of a button?
How frustrating would it be for an antagonist to do the same to the rest of the crew?
How difficult would this be to implement?
Conceptually, it is trivial.
Code-wise, it would involve stripping out the associated functions of detonation (and ensuring that this didn't break any dependencies), and also altering the UI to reflect the change.