I appreciate your position and initially I felt this way. However there are enough signals and inconsistencies from the TRON side of the equation that show there is an unignorable potential threat to the continued existence of the Steem blockchain. The participating witnesses came to decide that it would be better to proactively address this with a temporary and reversible soft fork rather than having to reactively address it with a hard fork which would be incredibly more difficult and divisive.
Here are some links that helped put me over the fence on this decision:
Tron Community in Uproar as Genesis Coins Used in Super Reps Vote - Feb 19th, 2020
February 17th, Justin Sun signaling the original plan was still in place, despite some talk to the contrary in the AMA on the 15th:
Justin Sun
Steemit to Shift Its Proprietary Blockchain & Token to #TRON Network. #TRON has just partnered with @steemit , a major blockchain-based blogging & social networking website to provide its network for #Steemit services.
February 18th Justin Sun tweets a link to a video which continues to indicate the intention to deprecate Steem:
Edit: I expanded upon the background as much as I could in this post: The Case For the Temporary Soft Fork