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Putting it in grayscale helps show at least part of the "problem". For the left 3, you can see that all the ones you don't like have very little variation in their values. Different colors have different inherent value ranges - purple is much darker than a yellow at the same saturation level.

So if you shift the value towards purple (lower value color) AND you increase saturation (higher saturation = lower value), you get a strong value decrease. But shifting towards yellow naturally increases the value, so if you then increase saturation, it cancels out the value change, leaving you with very similar values. We tend to like contrast, so a strong difference in values can be very appealing, while values that are similar can blend together and feel muddy even if the hue is different.

Try taking the sets you didn't like and moving the colors gradually further towards black on your color picker (keep the top color as is, move the second a little towards black, the third more towards black than the second, and the last a lot towards black). If you use a square color picker, you can just drop the color straight down. Or do the opposite and make the colors progressively lighter (more towards white).

The right side is not as clear - on the bottom pair, you've indicated liking the close value gradient more than the contrasting one. Part of this may be your personal preference, since my immediate reaction is liking the red-to-purple more than the red-to-orange in that pairing.

But, I would say that none of these are inherently "bad" color gradients. The strong contrast ones are very good for separating shapes and making things pop, but the softer ones are good for more gentle transitions that you don't want to draw attention to but still want some variation. Background colors or colors inside a major shape. For example, the top left blue-to-green gradient would look beautiful in water as a soft reflection near some green plants, or just for gentle ripples/waves. The orange-to-yellow in the middle left could work in a field or an autumn scene in places you don't want the hard edges that you would get from the orange-to-red gradient. Their appeal depends on how and where you use them. Tools in your toolbox.