I don't think the issue is so much "strikeouts vs. other kinds of outs" as much as it is "ball not put in play vs. ball put in play." It's just not the case that strikeouts or walks are the same "action" as a ball being put in play - in the former, there are 8 players just standing around whereas the latter involves at least a few other players doing something. And, of course, a ball put in play presents virtually infinite possibilities ranging from a great catch, a great throw, a baserunning blunder, a great slide, a comedic error, a rundown, or the team's left fielder deciding the cut off the center fielder's throw for some reason (ahem). None of which is possible when the ball is not put in play. (Home runs are a middle ground, since sometimes they will be close to outs, or be really cool and majestc, etc.)
Put another way, strikeouts and walks are only exciting in context. If the bases are loaded and it's the bottom of the ninth inning, sure, a strikeout or walk in that scenario is definitely going to be exciting. But balls put in play can lead to exciting outcomes regardless of game situation - it could be a 10-0 game but it's still cool when the losing team's center fielder makes an amazing catch, or still humorous when the winning team's first baseman lets a ball through his legs, etc.
You can't really have baseball without SOME strikeouts and walks, of course, and conversely I assume no one would disagree that baseball where the ONLY outcomes were strikeout, walk, or home run would be incredibly boring. There is a happy medium, but I'm among those who thinks the game is starting to trend too much in favor of the "three true outcomes." How to address that issue, to the extent one thinks it even is an issue, is another question entirely, of course.