Bold: Where do you see him say that?
"We recognize that the system is at the mid-point of its lifecycle."
What about that sentence tells you that it's from launch until replacement and not until discontinuation?
"We are not able to comment about the next game system at this time. It is now the fifth year since the launch of Nintendo Switch, and the total hardware sell-through has exceeded 90 million units. We recognize that the system is at the mid-point of its lifecycle. The launch of Nintendo Switch - OLED Model has also been contributing to continued sales momentum and we are now offering consumers three Nintendo Switch models to match their play styles and lifestyles, as well as a wide range of software. With this, we believe a foundation for growth has been laid that exceeds what we previously considered to be a conventional hardware lifecycle. With regards to the next game system, we are considering many different things, but as far as the concept and launch timing are concerned, there is nothing we can share at this time."
It comes from the context of the full statement that also addresses the question of the launch timing of a successor, so the mid-point then either implies a longer life until replacement or an unusually long life after a successor has already launched. A long life after the successor's launch would require continued strong software support by Nintendo themselves, but remember that one key point of Switch was to unify all of Nintendo's software development on one platform, because adequate support of two separate systems isn't feasible anymore. Assuming a cross-gen strategy that lasts for at least a few years doesn't make sense either, because Nintendo talks of Switch's successor as a system that can offer ways of play that can't be done on Switch out of the box. That's why I rule it out that Furukawa has been talking about the timeframe from launch to discontinuation, be it in 2022 or in any of the years before when he addressed Switch's lifecycle.
Legend11 correctly predicted that GTA IV will outsell Super Smash Bros. Brawl. I was wrong.