Who said anything about fair? When has fairness ever factored into business?
If a company sees an opportunity to make money, short or long term, they take it. That's just good business, right?
There is a cold calculation that happens.. If we do this, will we come out ahead at some point in the future? Yes? Then do it.
If "this" means hiring a ton of people that you might have to let go in the future, then so be it. That's how all companies operate, all the time.
The difference here is that the time between hiring and layoffs has compressed, and the bets that companies make are shorter term.. Hire thousands of people, drive massive quarterly profits for a while, then let a bunch of them go. Thank you for your service.
This is how a lot of existing industries work already.. Warehouse/factory work, seasonal work like construction and farming/fishing.. That's why those industries have unions too, because if this becomes a repeating pattern, the average worker suffers from poor job security and constant upheaval for the sake of corporate profits.
I said this in the discussion around Shopify's layoffs as well: as a worker in tech looking for a job, you need to start thinking about how much your role contributes to the bottom line, and also about the timing of your hiring.
If you are hired during rapid growth, then assume your job security is much lower, because your employer is making a bet, as opposed to planning for a calculated and safe long term expansion.