Correct speed of shuttle??

I disagree that most people simply don’t care.

Many hobby players don’t seek to learn how to control the shuttle. If I lift a shuttle at the front court it need to travel around 7m to not go out and fall down at the backcourt. If I need to clear a shuttle at the back of the court the distance is 13.4m.
The conclusion is that I need to hit the shuttle depending on the area I’m hitting from with a different amount of force.

Especially lower level players are also unable to control the shuttle by hitting it simply higher or with less force to make it be in, they blame the shuttle for being too fast, because they hit it long.
They use flat lifts and punch clears much more often because they simply didn’t learned the technique and strategy to play doubles right. Especially when it comes to learning without a coach many people are just focused on the result were the shuttle land. And people who can’t clear properly under pressure get the length by just hitting it flatter and brute force which has a higher risk to go long.
They also didn’t learned to use the whole court and each gap and most of them are obsessed by just hitting to the backhand rear court as only tactic to get a weak reply to score. If this won’t work they won’t have any clue to built up a game.I came this often across when I was hired as a coach for such groups.

The conclusion for them is to use a slower shuttle to get the impression to be better players by making less errors. They don’t hit too long, the defence on smashs by their opponents is easier and they have longer rallies, so they feel they are better players than they simply are.
Just ask this type of players how they define a good game and they will mostly say “long rallies”.