Nobody mentions how support items are cheap to begin with

The gold value isn't in line with its actual value meaning compared to a regular item like boots which it's value would just be extra movement speed so you have only slight advantages in situations that can occur that you can imagine more clutch escapes , poke management, faster rotations, etc.

Only slightly more situational power but is worth its value in gold.

<--- Value would be a champion power spike , extra damage stats , and lifesteal. Now you have the ability to kill with more opportunity available. Worth it's value in gold.

<--- Value being bonus HP which adds survivability, extra mana / HP regen, CDR, an unique passive and a unique active. Its active has enough situational value and power to play on par with items that have more than 33.33% gold value than it. Even countering them completely at times. This comes from masteries stacking with the base kits of support champions.

Redemption alongside other support items with similar situational power value should have there cost increased. Supports are given access to too much situational power too early in the game.