As Stan said, a better option than METV would be an ED visa. Tourist visas in any country are not designed for long stay "visitors" and repeated METVs indicate to Immigration that you are not a genuine tourist.
I just asked a friend in Melbourne - she has been trying to buy masks there & they are just not available. Bear in mind that if you are going to Oz, you will be staying in quarantine for 14 days in a hotel room with no opening windows and food delivered (all paid for by the government), so you won't need too many masks at least for the first two weeks. And yes, the limit for taking out of the Land of Smiles is 30. :)
I'm not sure it means anything about any specific public transport except, as stated in the article, that all public transport in the four Southern provinces - Pattani, Yala, Narathiwat and Phuket will be closed. It is probably a good indication that the rest of the country will soon implement similar restrictions though.
Yesterday I got the normal one year extension on my retirement visa at Sri Racha immigration - nothing has changed. This doesn’t mean that things won’t change if the situation worsens, so my advice is to get it done as soon as you can.
Henri is right - he should be personally credited with keeping the wheels of the Thai economy turning and shouldn’t have to comply with regulations. It is obviously you who is the arrogant one.