Actually it's not short sighted at all. The measures in place to prevent downgrading would require a hack of the boot loadeboot loader to be able to bypass. If you have boot loader it won't matter what firmware you are using as you will have kernel lvl code execution already. Therefore downgrading will be absolutely useless unless the user has a specific desire to be on that firmware to test something or what have you. I can link to the information on the wiki that confirms my statement if you wish but it is what it is.
I'm not going to get into a debate with you over how things are secured, but you are drawing incorrect conclusions and making incorrect assumptions simply because secured devices have many layers of protection and while you main gain access to a layer that say (to be simple), allows you to revert to a lower firmware, that access quite likely doesn't give you the control you need over the main system. It's really not that complicated to understand and there is a perfect, living and breathing example of that in the PS3.
We can now downgrade almost any console, but we still must downgrade the console in order to gain the access to run cfw and then re-upgrade the console to a higher firmware.
Different parts of a system have separate and unique layers of encryption unto themselves and that is relevant even moreso on the PS4 than on the PS3. Pwning on section does not necessarily give you the full access that you're assuming it does as they work independently of each other and are in separate sandboxes.