Working from home makes great economic sense for companies that can remain productive in that environment. It decreases burn due to real estate, and reduces commute times which can help with employee retention (especially for certain geos or demographics, such as parents). Worries about pandemic liability will also be a blocker for reopening many offices.

Covid has forced many companies to run the previously-risky experiment of whether they can thrive while remote, and it's unsurprising that those that can remain productive will use it to evolve + reduce costs.