Err… I'd hate to say it, but it is a legitimate criticism that there's a lack of single player minigames. One that was brought upon staying with their schedule instead of allowing themselves more time to ask "how would our base react to this or that" and fix it where ever possible. Would it suck to have to wait as far back as March or June 2019? Yeah. Would it be worth the effort? Definitely.
It's not Sakurai. It was the team who made this iteration in which this critique should be directed at.

Almost every melee fan will criticize future games for not being Melee-like. Its better to ignore them.