The OP talked about insurance with larger cartridges but did not show a single reason or scenario that backs up the opinion. I enjoy discussing honest opinions when they actually have a reason to believe it besides “because I read it on the toilet”.
In all fairness, it was falsely stated early in this thread a wound channel from a bigger cartridge was no bigger than one from a .223.
In fact, this is one of foundational premises I’ve read on here in support of the .223/TMK combination is other cartridges make a wound channel that is TOO big.
I think if we are being intellectually honest, a bigger cartridge what makes a bigger wound channel does in fact provide a margin of error for placement. If wound channel A is 4” in diameter and wound channel B is 7” in diameter, it stands to reason B can be a couple inches off the intended POA and still damage the intended vital area.
I will grant you the high likelihood this is not what folks are referring to with “insurance”. But the point remains it’s not a black and white issue and a bigger wound channel is still a bigger wound channel.
All this said it is my opinion, based on anecdotal observations, more game is lost/wounded because people 1) shoot poorly, 2) don’t truly understand anatomy/proper shot placement, 3) choose a bullet that isn’t best for their application, and 4) are poor trackers. Choose of cartridge ranks pretty low in order of importance IMO.
Edited to add 1 and 3 can be tied into cartridge choice, but the level of significance can be highly variable.