Scrum lends itself particularly well to distributed/remote teams. On average, working remotely increases productivity. Therefore, the optimal "seating arrangement" for a Scrum team is wherever they feel like working from that day: home, a coffee shop, a mountain top, the ISS (if they can get wifi up there...)
Here's just one of many articles you can find on the subject:
A 2-Year Stanford Study Shows the Astonishing Productivity Boost of Working From Home
Instead, the robust, nearly two-year study showed an astounding productivity boost among the telecommuters equivalent to a full day's work [per week]. Turns out work-from-home employees work a true full-shift (or more) versus being late to the office or leaving early multiple times a week and found it less distracting and easier to concentrate at home.
Additionally (and incredibly), employee attrition decreased by 50 percent among the telecommuters, they took shorter breaks, had fewer sick days, and took less time off. Not to mention the reduced carbon emissions from fewer autos clogging up the morning commute.
Oh, and by the way, the company saved almost $2,000 per employee on rent by reducing the amount of HQ office space.
That's exactly my experience. My personal suspicion is that a minority of workers experience gigantic performance gains (in my case, double or more) while a majority see smaller losses, and it averages out to a small gain. The Stanford study aligns:
More than half the volunteer group changed their minds about working from home 100 percent of the time--they felt too much isolation.
In this study, working from home increased productivity by 13% overall, and 24% among those who chose to continue working from home. Other studies have produced similar results. At the other extreme, another study found that open floor plan offices decrease productivity by a similar amount. The bank of face to face desks you describe is the worst possible working arrangement.
Remote is also a good way to attract top talent. From the SO 2017 Developer Survey:
When we asked respondents what they valued most when considering a new job, 53.3% said remote options were a top priority. A majority of developers, 63.9%, reported working remotely at least one day a month, and 11.1% say they’re full-time remote or almost all the time.
My suspicion again: those 11% are disproportionately rock stars with a lot of negotiating power. For them, opportunity to work remotely may substitute for astronomical salary requirements. (Compare the prices of an acre of land in the middle of nowhere, Montana vs. downtown San Francisco.) In addition to increasing productivity and saving money on rent, going remote may allow you to hire more and/or better developers for the same salary.