I don't know...I went to Megadeth in an outdoor venue. I was in the pit and hardly anyone were wearing masks, there were people whom were. Those who did not were buzzed, I ended up almost getting peed on by this drunk guy who decided to whip it out and release right in the pit. I don't know what happened after because I saw him reach down and I immediately split to the other side of the pit. I also saw a lot of people passed out drunk.
I then went to the Unleash The Archers show at a small venue that was packed to the brim with about 100-200 people. There were guys not masked at all making a mosh-pit which pretty much was the entire venue size, screaming and yelling away. I kept mine on, but lowered it mid set, and the band didn't seem to mind at all. They were actually making fists with people, and these unmasked guys. No vaccine passport or negative test required.
It's looking like now it's up to whomever wants to take that risk, and many people are by attending the shows. Even the musician themselves know that risk and are catching it and dealing with it.
But, also, Dream Theater are not easily replaceable as their music is so complex to learn a full set worth of songs on such a short notice. The vocalist you could find a temporary much easier, but it does change the tone of the band and in Dream Theater's case, it changes the tone immensely. At least, that's what The Shattered Fortress shows revealed to me.