More likely they will hire more contractors in the fast ramp-up after things start rolling again (quicker to onboard a contractor).

Contractors are the first to get filled and first to let go.

I disagree. A benefit of having a contract worker is that they don't show up as a recurring cost. I used to work at Morgan Stanley (Ruth Porat's previous CFO gig before Google) and around the time I left, the tech organization was roughly 70% contract workers. This was well after the crisis, and the company was laying off full time employees in at least one wave each year, while the ranks of contractors began to swell.

My breaking point there was actually that despite having a fairly senior title, I was being called in to do tons of mundane work on the weekend (checkouts after network/firewll changes) because they would have to pay contractors to do it on the weekend, and that was not allowed.

I definitely felt toward the end that you had considerably more job security as a contractor than an FTE. So much so in fact, that after being fed up with weekend and late night work, I probed to see if I could go the contractor route. Then I found out that they got paid by the "day" and not even the hour, and the rates they were paying were finely tuned to make them more or less break even in terms of FTE pay when considering benefits and such.