With the config screen being blocked with Minecraft 1.15 do we HAVE to have the ClothAPI installed as well? Seems pointless since we can't actually adjust any configs from in game in 1.15.

you can edit the configs, that's what cloth config is for.

Running Fabric yes you can edit them in game, but running Forge you have to edit configs manually from the config folder for Minecraft version 1.15. Unless I'm missing something somewhere where Cloth adds a screen somewhere in Forge version.

Cloth doesnt add a screen, but it provides a screen for light overlay to add a screen.

Open up the mod list added by forge and edit the screen.

Don't worry, I also think it is a pity that most mods don't have a config screen because forge doesnt have one yet, I think when forge finally adds their config screen mods will start to use them.