Now that we are getting security patches through the play store thanks to project mainline should I even care how many years of security patches a phone brand is offering?

Nokia no longer releases security patches for my handset Nokia G20. What I do is I go to:

Settings>Security>Google Play system update

and install updates as soon as I get one.

Thanks tothis feature I can still use my phone without worrying about security.

Now that we are getting security patches through the play store thanks to project mainline should I even care how many years of security patches a phone brand is offering?

If the answer is yes please explain why.

Your opinion will help me while choosing my next phone.