At his age, and with jet lag, there's a good chance he'll catch a juicy bug. Oh, that's right. God will send ministering angels and protect him from all Satan sent microbes.
He's in great shape for 93. So was my mom's aunt at 94. The reality is at that age; especially when someone has the responsibility and stress of leading a large organization it takes it's toll. President Nelson could last another ten plus years but he will fall out of sight. Oaks and Eyring will be the visible ones until they have problems. Then we're back to the situation the First Presidency was in with Kimball, Romney, and Tanner all unable to run the church. I think the church has been through most the scenarios that can happen. Really the prophet is more of a mascot than anything. The church is ran by a committee. There will always be enough apostles to run it. The church hires experts to run all the finance and legal stuff much like a royal family does. I doubt any of the Windsors could really run the monarchy and all the assets they own. The church is similar.
I imagine that Oaks is already pulling all the strings. He is de facto the CEO of the Corp. Nelson is more like an honorary Chairman of the Board to be wheeled out for ceremonial purposes.
Brother Russ started the tour with a speech to the faithful last night here in the UK. I can't find a trace of any LDS reporting of that speech-zip, nothing, not even in the usual sources. Maybe they are still transcribing Nelson's sacred words to brass plates in Reformed Egyptian?
Nelson will rock up, he'll give the usual empty words, a low grade pep talk, with some mildly humorous story about his past, then they'll close.
Members will leave and if they're honest they'll wonder what the heck that was even about and was it even worth attending?
The problem for LDS leaders is they have no meat to give in talks anymore. They can't give any revelation because it is highly likely to conflict with science, philosophy, or history (even their own). As a result everything is fluff.
Hour after hour of fluff talks - 'Be Good' but don't ask for a definition of good because we're not sure.
They really are prisoners of their own making - like the Windsors. But they have a choice, they could come clean and because they don't i have zero sympathy for any of them.