not to say that building taste and comparing and contrasting with others is obsolete, i couldn't believe any more the opposite - it's just important to always realize that even the most concrete of foundations you can create in taste will still be subjective.
I would argue that you can at least try to look at something in a more prosaic manner and exert your faculty of abstraction. You sometimes play a rich game that has an alluring scoring system, a stage/enemy design you would describe as impeccable, even with a sterling atmosphere, yet it fails to capture your interest. While another game, despite some apparent flaws such as flicker, slowdowns, sometimes questionable hit detection, weird difficulty spikes, completely useless power-ups etc. simply wins you over for one quality or another. Point in case: Raiden DX is without a doubt a superb game from both a survival and a scoring perspective, it has phenomenal visual appeal, lots of character, offers several modes, rewards both memorization-inclined players as well as dexterous ones and so on and so forth. However, I find the medal chaining to be maddening and the Expert course way too unnerving to be truly enjoyable since I'm sitting on the edge of my seat the entire time through due to the bullet speed. That's just my "problem", though, nothing I can blame the game for. It's only fair to differentiate between personal predilections and quantifiable traits of a game. The latter will naturally still lead to some debates ("The game has impossible checkpoints and is thus badly designed!" "No, it hasn't! Every checkpoint can be overcome with a bit of practice."), but it's evidently on another level than simply disliking a concept/artistic vision/sub-genre out of principle/personal preference.
Both excellent points - as kitten alluded to, it's important to recognize the distinction between objectivity and concreteness. Recognizing that your views may not be shared by others does not stop you from breaking down and analyzing the specific reasons behind your taste/distaste for a game. At the end of the day, it's your decision how much you care about certain positives/negatives and whether you even consider a certain factor to be a good thing or a bad thing.
For instance, one reason I like Dragon Blaze is the simplicity of its scoring system - it's more involved (specifically, more rhythmic and aggressive) than the basic "shoot enemies to get points," but 1) it's still easy to comprehend and trace deviations from your expected score back to the actions that caused those gains/losses, and 2) the game has the visual feedback to show you where your score is coming from (gold coins, tech bonuses). But some people like more complex scoring systems with many hidden variables that require the player to experiment and discover how things work. Neither's "objectively" better than the other, but that doesn't stop players from thinking about it and figuring out their taste beyond a nebulous "I like this game and I don't like that game."
You know STGs are in trouble when you have threads on how to introduce them to a wider audience and get more people playing followed by threads on how to get its hardcore fan base to play them, too.
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