On a related note, in all those discussions about how different singers preserving or losing their voices, it would be really informative to compare their touring schedules. From my perspective, based on my - admittedly very limited - personal experience, full gas singing 5-6 days a week is just too much, something you can partially recover from when younger, but not really when age hits you. IMO, spacing of the shows is an elephant in the room as it is rarely brought up when talking about singers' performance decline, but I suspect it is one of the major factors. But more data would be needed to confirm (or refute) this claim.
You can certainly look at Rush as a reference. I don't remember exactly what tour it was, but there was a point where they stopped doing shows on consecutive days just to make sure Geddy had time to rest his voice. And even then, while on tour, I recall him saying that at least on show days he kept his speaking to a bare minimum, once again to preserve his voice. Now obviously DT doesn't have the draw that Rush does - at least in North America - so that's a factor, as is the increase in expenses post-pandemic, which Rush never had to deal with. So I'm sure that if it were up to them, they'd space the shows out more for James' sake, but it's quite possible that's just not financially feasible.