(I'm not the OP but I'm guessing this is what they're talking about?)
Plenty of digital services have the ability to do this, but don't. Honestly, I think the primary reason is that it's extremely offensive; it feels like saying "we're charging you more, for no reason, other than that we think you'll pay it".
The trick airlines use is to make the price discrimination transparent in a way that a customer feels is "acceptable" - time variance, seat variance and addons etc. It adds the same level of price discrimination, but because it's not directed _at the person_, the customer begrudgingly accept it.
The price changes according dynamically according to demand.
First, you can use the airline's strategy to your advantage by planning early. It doesn't feel as unfair because everyone gets the same terms and the system is transparent and equal
WaPos daynamic pricing is simply maximizing value capture, without any way of a consumer benefitting. It's 100% lose-lose for the consumer. You always pay the maximum you are willing to pay. No discounts!
I was just answering OPs question about how airlines were transparent about their system and decided to answer it factually.