Nokia Mobile is obligated to release kernel source codes of its Android-running smartphones, and that is what they are doing. Even though a small part of fans would like to have a bootloader unlocked, so they could further tweak their beloved smartphones, kernel source codes is max they can get. In the past year, Nokia mobile launched many smartphones, but not so many source codes. Now they are catching up by releasing kernel source codes for Nokia 7.2, Nokia 6.2, and Nokia 4.2. If you by any chance need those files, you can find them on a dedicated Nokia page.
Interestingly, you can also download kernel source code for the Nokia 8110 4G, which is nice. Nokia 800 Though and 2720 Flip are missing there also.