You're Correct!

The longer a golf club gets, the more difficult it becomes to hit well. This is because as you swing the club around you, the movement that you make gets exaggerated into the club head. If you are slightly out of position and using a shorter golf club then the club head is not as out of position as it would be if you were using a longer shafted golf club.

Therefore, hybrid clubs were originally developed to help golfers hit longer golf shots more successfully. They originally replaced your 3 iron, the longest length iron, which was the most difficult iron to hit well and to achieve a centred strike from the club head.

Hybrids were designed to give golfers a larger club head on their longest length iron. The larger club head initially means that the club face has a bigger sweet spot than the smaller iron head. The sweet spot is the area where the golf ball achieves most shot length and accuracy if hit from. Having a larger sweet spot to strike from makes it much easier to achieve.

The larger hybrid head also means that the weight can be positioned further away from the club face and doing this results in greater forgiveness and height to the shots that are hit with the golf club.

As hybrids became so much easier to hit high and well, more loft options became available so that golfers struggling to hit any of their irons could replace them with much easier hybrid options. If you struggle to hit your short irons high and you tend to mis-strike them, then replace them with hybrid options and improve your golf instantly.

Short irons need to be hit high to achieve their purpose. They are used to play shots on to the green that stop on the green. This is achieved by hitting the golf ball high so that it lands from a very vertical position and therefore stops as it is moving downwards rather than forwards. Mis-hitting this shot will produce a low trajectory shot that lands and then runs forward due to the low angle that it hit the green at. The shot will therefore travel through the green, rather than stopping on it and forcing you to have to play at least one more additional shot. If this happens on every hole, that is 18 additional shots just from not being able to play your short irons well or high.
Replacing your short irons with hybrid alternatives makes it much easier for you to get the golf ball high and into the air. As the club heads centre of gravity is further away from the club face, the hybrid produces a higher trajectory shot, getting the ball up into the air and therefore making it land at a much steeper angle so that it stops on the green without running through it and meaning that you do not have to now play an additional shot to get the ball on to the green.

Hybrids were originally created to replace long irons in a set of golf clubs, specifically your 3 iron, as it was a difficult club for club golfers to hit well. Hybrids have evolved so that you can replace any loft of club in your bag with them.

Your short irons are used to play high, short golf shots that stop on the green. If you mis-hit your short irons and struggle to get them into the air, then you can now replace them with hybrid alternatives that give a higher trajectory from them, making it easier to hit a high, short shot that stops on the green.

Hybrids are constructed in every loft option so that if you struggle to hit any of your irons well, you can replace them with a much easier to use hybrid. You can buy a full set of hybrids so that you do not have to play at all with irons.