Probably because these days it's almost a foregone conclusion that updating will be necessary since board partners no longer think they need to work out all the compatibility issues before releasing a model like they used to do. They figure they'll release as they go, which means often hardware incompatibilities aren't found until the product has been leaving shelves for some time already.
That, and like a lot of people, he may have concerns regarding the Meltdown and Spectre side channel vulnerabilities that they are saying require firmware updates to bolster security against. I for one am not installing the latest firmware against these as I am unwilling to trade off my performance when I already know these are only critical if you have already allowed the prerequisite malware to be present on your system in order for these vulnerabilities to be used anyhow. No thanks. I'll just keep windows patched and keep my malware definitions up to date.
But for other reasons, I am always totally for being up to date if hardware or performance considerations are in play.
If you can't figure it out from this, then I guess you need to find somebody with experience updating bios and have them help you.
https://www.youtube.com/watch?v=CG63bPkXqR4