I think the real question is, SHOULD the Switch reach 150M sold? Meaning, is it in the best interest of Nintendo to sell that many? Fact is, the only two consoles that reached 150M units sold were succeeded by the worst selling items for that company in those categories. The PS3 is the worst selling Sony home console, and the 3DS is the worst selling Nintendo portable. Perhaps Nintendo should focus on continuity of the brand instead, and not focus so much extending the life of the Switch that the successor suffers as a result. It's probably better if they sell 130M Switches and 100M+ Switch 2s, than 150M Switches and 75M or fewer Switch 2's.
The cause of those lackluster successors is arrogance, the belief that they could sell anything after they've been so successful. Selling 130m or 150m wouldn't change anything, because both numbers are well above the threshold of a company possibly becoming arrogant. So what actually matters is to stay humble.
What's clear in light of Nintendo's first party development pace is that Switch has to have a long life. Ideally, the launch of the Switch successor is timed to closely coincide with completed games of EPD teams. Mario and Zelda teams are on track to get their respective second Switch game out in 2021 after both had launched their first game in 2017. Accordingly, Nintendo should plan for a Switch 2 launch no sooner than holiday 2024, so ~7.5 years after Switch's launch. Given how little Nintendo has used of the price cut and revision options until now, Switch definitely has the staying power to go another four years before replacement.
So when you put all of that together, aiming for 130m instead of 150m would actually be a move of arrogance, because it would result in a rushed successor that lacked big Nintendo titles early on. That's what Nintendo did with the 3DS (originally intended to launch holiday 2010, but production problems forced a delay to early 2011), so for the DS it would have been smarter if Nintendo had aimed for a higher sales total in order to allow for a smoother transition.