Indeed, it is not. However slowing down the pace of life generally has benefits beside being less energy intensive. Many people's mental health and quality of life could be significantly improved by removing the stress of the modern fast-paced life.
As a personal example, I used to work quite regularly in Belfast doing a Monday to Friday and back home for the weekend. The options were to either fly or get the ferry. Unless I had some specific reason that I needed to be home for part of the Sunday I would always get the ferry out and fly back. Even though the journey by ferry took about three times longer, it was always the less stressful of the two.
I too have weekly commuted, and to be honest while 2 years of it was wearing (it had to end then, because that was the length of a short-term work permit in Switzerland at the time, and going past that involved complications with tax domicile and similar) I actually enjoyed it and miss it. So I'd not assume that it would impact everyone's mental health in the same way.
Like daily commuting, what really made it work for me was reducing it to 4 days a week with Fridays from home.
If people are happy to do that (I took my job in the full knowledge that is what it would involve) and the environmental issue can be solved, why not?