You are awfully eager to excuse cops shooting a man to death in his own home. So far there is no evidence of wrongdoing to support the execution of the raid. When such a radical mode of entry is used the police should be darn sure there is just cause, well researched and double verified, and that all alternative means of effecting an arrest and search are explored. Dynamic entry should be of absolute last resort, not first option taken as it seems to be done in these stories.
I also think you are dead wrong in the supposition that SWAT raids stop when drugs are legalized. Even if drugs are legalized, SWAT teams will continue to exist until there is political will to disband them and so long as SWAT teams exists they will be used for what ever purpose they need to justify their continued existence and funding.
There was evidence of wrongdoing or no search warrant would have been issued. According to the media, evidence in the phone and computers were siezed at Guerenas house. You are assuming that this SWAT Team, which is indeed large does not do it’s homework. They are briefed by other investigators and do their own intelligence gathering. Alternative methods are always explored. SWAT is not the first choice always but you are assuming it was. Were you there for the briefing? No, neither was I, but I have sat through many, probably will do another soon.
If you had read my posts, you would see that I posit that SWAT raids would be drastically reduced with the onset of legalization, not eliminated completely. They have a purpose and it would be hard for any agency to justify using them for anything less than high risk endeavors.