Here is why supports are not fun to play.

Every single champions in the game but enchanters have items to amplify their strenghts OR help cover a weakness.

For example,

Tanks usualy have low waveclear. So they can get to help cover that weakness. Or, since they are a tank, they could buy to increase their already strong CC

ADCs have a long range, so they can build to further increase that strenght. Or, they could get a to help with the fact they have trouble dealing with enemies who come close to them.

A champion with DOT could get a to increase the said DOT, or they could get a to abuse the slow.

But when it comes to support, their kits scale too badly and are just not impactfull enough for them to make those kind of decision. It looks a little more like this.

As a support, your heals scale of AP so you could get an item like to heal more. OR... you could get and create a huge area that heal your allies for a lot and deals damage to enemies. Redemption won't bring anything to your kit. But it's simply more effective to get redemption instead of something that amplify the said strenght of your kit.

If the enemy has a lot of damage, are you better off building something like to make YOUR shield more impactfull, or would you rather get a 600 shield for all your team with ? Of course locket will be more impactfull.

Support items create a strenght on their own to cover the fact supports are weak. Some other champions started building Redemption and Locket just because of how strong the actives are, but these actives don't feel as overbearing when put on a support because they just cover the fact they are less usefull than other champions.

Put a Full AP Janna and a Janna with full support items against each other in a fight and tell me wich one of them is going to do her job better as a champion who buffs and protect her allies? Full support Janna will do better. But hey Janna's WHOLE KIT scales of AP. So shouldn't she be more usefull? No. Because when you build to amplify Janna's strenght in her kit, she is not strong enough to compete with the version of herself who take item actives. ITEM ACTIVES ARE MORE IMPACTFULL THAN THE ACTUAL KIT OF THE SUPPORT.

This has to change. There is so many unique champions who have an impact on the game in so many diffrent ways when they are in the good situation. Throw a Orianna in a teamfight you'll see what I'm talking about. Look at a Tryndamere or a Nasus splitpushing and you'll see that this is what they don't need item actives to do it well. But a support? In any situation they have one job to do: Dump all their actives and shields on the most important target for the enemy team and hope they live. If a support is alone he is nothing. Why can't supports be usefull with their own kits and be considered as champions on their own with strenghts and weaknesses? They have the worst scalings, base stats and spells in the game just so no one considers taking them anywhere else but support. And when they have a way to actualy build in harmony with their kits strenghts and weaknesses, their scalings are gutted (See Lulu and the way they reduced the scaling on her MS boost by HALF).