I don't want to take a side in this argument (pro remote vs offsite vs hybrid), but productivity measurement in agile software development is hard and I have never seen it done well, so it's hard to trust these measurements with this decision.

Another issue is the author's conscious and unconscious hidden biases and agendas. If a research is ordered by a video chat software company, you bet the result will be different than if it's paid for by a coworking space provider.

Similarly, you'll have a different result if it's done by a SF company who needs to justify their expenses vs. by a remote team headed by a manager from the woods in Wyoming.

By the third citation, you lose the source of the study, only have the clickbait outcomes like "86% productivity drop by onsite work", so I'm in the camp of "do whatever feels right for your team".