Can someone explain this? I have DKMS enabled because I use the proprietary nvidia drivers. Also all my drivers are kernel modules. I feel like I'm missing something here, though.

If you use proprietary binary code in kernel, it runs with high privileges and can be used to provide remote root access to your system. Don't worry much about it, your computer most probably already runs proprietary binary code with such high privileges before your OS boots.

While I’ve certainly enjoyed running all compiled-in kernels in the past, I think it’s a bit inflammatory to suggest that there’s no need for modules, when literally every major Linux distro I have ever seen in production (outside of certain embedded devices) has a modular kernel. There’s a good reason for that...

The Cybersecurity Advisory link in the first line of the article is worth a read for a greater insight as to why it might be more than just 'pfft, nothing to see here' regarding kernel modules

Can you please explain the security issue with module-enabled kernels?