Why only a fraction of what i paid an out-of-network provider counted towards my deductible?

Went to see a out-of-network psychologist which charged me $400 for a session (I paid already. And yes I know it's pricey but lets keep that out of the discussion). My insurance has a $1000 for out-of-network, after reaching deductible it will be a 30% co-pay.

Submitted a claim it came back with a "Discount amount" of $302.47, and "Covered by Plan" and "Deductible amount" is $97.53 (i.e. $400-$302.47). And when I check my deductible account it only increased by $97.53

So I guess for out-of-network services, maybe what count towards deductible will only be what insurance deems a reasonable price for the service, instead of what I have actually paid/charged? This is the first time I use out-of-network so it came as a surprise to me, and obviously that really sucks… Just trying to understand. Attached a link for screen cap of the claim: