A server whose uptime goes to X years is a server that wasn't updated in X years. I'm proud of my old XigmaNAS (FreeBSD) ~15 months uptime years ago that only a blackout did interrupt (yep, I had no UPS), and I write this as a mostly Linux user, but I'm not sure it's a good thing to aim for in production or in anything connected to the Internet.
In case something goes wrong, you might have to restart anyway. So you better exercise that process to know it works. Also, I'd rather get really good at dealing with the first day of uptime of a system, then discover what the n-th day brings for ever larger values of n for the first time ever.