Forgive me if I sound angry here, but let me just vent about how awful this change is. He cited the reasons for the new version being more useful being power and range. First off, his f-smash was fine in Brawl. It moved him forward a tad, so while it had less range than this version, it had a decent amount. There's also the factor that if range was truly a problem, they could just have him move forward a little bit more. It's not that hard to fix the range issue. He also noted that he uses his body, rather than extending an attack like his fist, making him more vulnerable. This would be true, if that wasn't already dealt with in Brawl, where he was given super armor on its active frames specifically for that reason. His last reason, the fact that its power wasn't useful enough, could easily be negated by just making his shoulder bash more powerful.
And then there are the parts about this move that make it functionally worse. Firstly, it's significantly slower. Whereas in Brawl it was active on frames 9-11 and ended on frame 44 for a total of 33 frames of endlag, the new version is active on frames 18-19 and ends on frame 66, for a total of 47 frames of endlag. So, yeah, it's pretty slow. And then there's the next factor: It doesn't always work. Because the attack starts so late into the animation and isn't active for very long, the hitbox only comes out when the fist is fully extended. And because Wario leans forward so much, his fist will often be extended completely past his opponent if he's too close to them, resulting in harmlessly punching the air behind them and leaving himself completely vulnerable to punishment. Its range is a little longer than Brawl's, which could have been compensated for by increasing the (already adequate) range of Brawl's version. It's more powerful than in Brawl, which would only require making adjustments to its knockback values that they already ended up making anyway. It's a functionally-inferior attack that removes any reference to Wario's own series and tries to address flaws which could have easily been addressed by making slight adjustments to the already-existing move. That is why Sakurai's explanation does not fly with me.