Shadowkeep should be free or cheaper.

[DJukor]

I own the expansions. This is just my opinion based on the content of it.
All expansions add something substantial to the game aside from the campaign.
Beyond added Stasis Witch Queen added Weapon crafting and Light Fall Strand.
Shadow-keep added nothing important to the game-play or can straight up be skipped as it also adds little to the narrative and its base weapons are also kinda useless as they have less perks than average.

[trukr]

Right now people can get Shadowkeep along with Beyond Light and Witch Queen for $15, there are sales pretty often.

Our only say in price is what we will or will not pay. It's their IP, if no one buys it they will lower the price or not care.

Edit: Shadowkeep also has Garden of Salvation and Pit of Heresy.