My view is that the same people who pulled off xz are putting God knows what in the weights

That doesn't make any sense. Model weights are literally just numbers you multiply by. To imply that it's any way even remotely comparable to the xzutils build process is...

Well, I would be very technically impressed if someone managed to achieve any form of code execution, especially given unknown levels of quantisation post-release whereas xzutils was interesting mostly due to obfuscation.