I think server parts shortage + mass influx of new players (from WoW, streamers and such) has tied their hands. Maybe they could've not packed the servers to the breaking point, but at the same time, who's gonna say no to money?? They did mention they've optimized it as much as they can but I feel like it will be another year or so before the parts shortage becomes less of a problem, but if YoshiP had told people "the expansion has been delayed for a year", players would've rioted.