I am starting to notice a theme with Donkey Kong Junior and Donkey Kong 3. When people first start playing Donkey Kong Junior they actually like the game. Most people who like the game are the casual players. When people first start playing Donkey Kong 3 they don't care much for the game, and so many of the detractors of DK3 aren't really that good at the game to begin with.
That changes though. Once people start taking Donkey Kong Junior seriously a change happens. Now they have to start point pressing for about half of the game, and the motions are extremely repetitive. Now the high level play for them becomes extremely boring as you do the same motion over, and over, and over, and over again. So people who play it at a high level are not as positive about the game. Now personally I am cool with the game, and the repetitive point pressing doesn't really get on my nerves, but I am more of a unique case. At least half of the high level Donkey Kong Junior players really don't like the game.
For Donkey Kong 3 the opposite seems to be happening. Most people who take the game seriously seem to like the game, and still have a favorable opinion of it. Now there are exceptions to the rule, but a good 80 percent of top level players seem to like the game. Words like fun and challenging are thrown around.
To make an analogy, Donkey Kong Junior is like heroin. The first try is great, but after many uses the fun of the drug is completely destroyed.
Donkey Kong 3 is more like beer. At first the taste isn't that great, but once you acquire the taste you have no problem drinking beer, and it still does the job even after enjoying beer for decades. Of course you can become an alcoholic and the fun is ruined, but you really have to work hard at that to happen.