Stranger camp wisdom is a whole genre, lol. Some guy once told me my camp chair was trash because the legs kept sinking into sand, now I carry these little plastic feet things everywhere I go.

Why do ads always leave out the messy parts that actually matter?

Yeah, "copy-pasting the same weak code" is exactly what's happening. I've torn down a few commercial badges for a client and it's scary how often the update mechanism is just the same insecure pattern with a different hash slapped on top. The real problem is nobody's checking the bootloader's rollback protection or even verifying the signature chain properly, so once you find one flaw, it's basically a master key for half the vendors at the con. Just assume every badge that ships with an STM32 or ESP32 has the same lazy update code until proven otherwise, and check the datasheet's reference firmware first cause that's usually the source of the copy-paste.