It would definitely require much patience to go through 700+ episodes, as well as each one for over 20 minutes, plus the movies and specials.

Not counting the movies and specials, though, it would take over 14000+ minutes which is 9 days.

No one has the time to watch every single anime episode for 9 days straight with no interruptions, so yes it's too long to go from Pokemon! I Choose You! to Episode N.