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Not really a comment on who has better shows, it's all personal opinions, I've liked Xbox's more but I am an Xbox fan for a reason.
I don't really judge shows in hindsight because at the end of the day, these showcases are nothing more than marketing tools and as such it's the marketing which should be judged, nobody can predict for certain when a title announced at a showcase will release or what quality it will release at but they can judge the quality of the marketing at the time of the showcase.
Great announcements remain great announcements even if the final product hasn't yet released and changing on hindsight will mean changing a lot, lets use 2020 for example, if you change your opinion on the show to (lets say average) because the games have not yet released but then the games do release (to critical acclaim) does that show suddenly become one of the best shows ever?
Marketing is wholly separate from the development team, we should be judging the marketing team. It ain't like we can play any of these games at the showcases until their release months - years later so we can't judge quality of the game itself. Imo it's irrelevant to the marketing quality if the game has yet to be released.
2018 and 2020 did their jobs in generating excitement for the Xbox brand and renewing faith in it, it's not the marketing teams fault that the games have not yet released, but I would say the marketing should be showing these games more often or giving updates on their development progress. At the time I can only judge the showcase on what I was shown.
Sony's E3 of Dreams was considered amazing at the time, Shenmue was a huge hyped announcement but a disaster on release but it doesn't change that at the time the announcement was hugely well received. I judge the showcases on what I felt at the time and not what I feel now years later because that will constantly be shifting. Shenmue being a dud doesn't change how well received the showcase was.
