I'm at Muang Thong Thani Immigration K Counter right now.
Today, they are "very serious about residence, Na". That's the TM30.
You HAVE to have the printed form if it was completed online by a landlord. If, like me, you're staying with friends in various places as you travel you have a lot more work to do. See below.
Your friend has to prove that you are staying with them. There are several ways they can do this but they seem to require some legwork. (I don't know what I'm going to do as my friend is working in Phuket until after my visa expires.) I've included pictures of the forms they'll require.
Also, there are new forms you're required to sign saying why you're staying (C-19 related) and that you understand the penalties of overstay.
EDIT: I added pictures of the new (to me) forms as well.
TLDR : Answer Summary
While at Muang Thong Thani Immigration, the user emphasizes the new strictness surrounding the TM30 residence notification, particularly for expats staying with friends. A valid printed TM30 form is essential, whether completed online by a landlord or otherwise. Friends must prove the stay through various documents, which can require significant effort. New forms concerning COVID-19 and penalties for overstaying must also be signed. Users describe challenges faced regarding the TM30 and share experiences about the bureaucracy involved in visa extensions. There is a strong sentiment about needing better clarity and cooperation from officials.