I have a very long standing doubt. Many people go for upgrades to include more channels in their sound stage. From 5.1 to 7.x and then to 11.x and so on. But what if more speakers are added into a say 7.2 set up in existing channels, given the sound signals are just shared, would just get more volume but not upmixing: BUT then we dont have many content that are meant for more than 7 channels either even for 2022 standards. So would it make sense to add more speakers than buying a costlier avr amp with more channel support?