Unless you know what it is and have REALLY strong feelings about that, nope. You wouldn’t be here asking otherwise. You’re fine.

only the truly ascetic stallman monks can main libre stuff

I was learning what they are actually and I don’t see any point of using linux-libre.Nowdays Linux kernel loading firmware for device from packages called “linux-firmware” technically is binary files located in ur filesystem.Linux libre project just removing mechanism of loading firmware dynamically,does it make device free? No they just don’t work.Devices which work with linux-libre for example WiFi dongles contains already firmware on WiFi chip itself and not loading from ur computer.In fact u even loosing security patches from vendors which u can get as updates for all devices.Linux libre project even removing warning about that u are u are using vulnerable firmware.Blobs which now located in kernel code itself is header files with some amount of arrays number arrays.Also not all firmware files works in once,kernel loading only needed one for hardware installed in computer right now So in conclusion I would not use such kernel,problem not in kernel ,problem that vendors don’t share source code for devices.Project linux libre not okay with dynamically loading firmware from filesystem buy they are okay with firmware which installed on devices which work without dynamically loading.It’s weird and sounds hypocrisy

if you want to be fully foss then sure but you’ll probably find shit works less reliably with it. ymmv

Use whatever works for you. Perfect is the enemy of good. If there was anything better or just as good as free software as the few blobs that are in there they would be replaced since blobs are a pain to work around.

No.

If your hardware supports linux-libre and you don’t consume DRM content (If you don’t know. Widevine is the cause), it’s better to use that. If not, then you can use Debian/LMDE which can only use the blobs your hardware requires.

My only reason for wanting to stay with the stock kernel is because its better maintained and gets audited more

linux-libre used by Trisquel GNU+Linux which used by FSF. So don’t worry.

Can the blobs from the stock kernel be a vulnerbility?

This is not the thing to worry about. Vulnerability is normal because we are human. What is worrying is that blobs are non-libre and you are dependent on the blob developer to care. If the blob developer cares, then great. If not, then you are done. Also, this is a matter of trust. We cannot know what blobs are doing because they are non-libre.

Since you are already using Libreboot, you already have (proprietary) microcode updates installed. So I think it shouldn’t be a security disaster with Linux-libre (that assumes that you keep your Libreboot updated). Worst thing that would happen is that your hardware won’t work. That’s also the best thing that will happen. The blobs are just firmware that gets loaded on a device that needs it. If you have the device, it won’t work without blobs. If you don’t have it, the firmware is not loaded so the outcome is not that different from regular linux. And also reading from comments there are some blobs for enabling DRM content. I guess that’s not mandatory.

Though imo Linux-libre is pointless. For noobs it’s a potential security disaster and skilled users would be better off compiling their own kernel with just the features they need to reduce attack surface.