This is just a thought experiment. No one's planning to get rid of them.
To clarify, when I say TMLs I mean these four units:
I feel as if these units really only exist as a "noob check", to kill and/or do severe damage to new players who don't know of their functionality or how to defend against them. You can also punish players who forgot to build TMD to protect their T2 mexes and power, but that's about it.
Sure you can build 15 of them in a stealth field late game for a surprise attack, or snipe the occasional fatty, but would anything really change if we woke up one day and these units were gone?