The oldest bike, the 2016 hard tail mountain bike, has over 4000 miles on it right now.
The road bike (the one you indicated that I should be having problems with annually because of notorious cable problems with Shimano shifiters) has around ~2900 miles.
Neither are a problem at the moment so I'll keep riding them as is. The obvious part is that I recognize that I don't need to change my cables and housing on an annual basis based on what some guy on the internet says. And as a bonus I keep more money in bank account.