Lol.
The "extra possession" thing is a load of shit. You get that possession no matter what; it's just a matter of which half you get it in. So there's zero advantage to the number of total possessions.
If you win a coin toss you are winning the right to decide when your one and only guaranteed possession is. Do you want it right away when the game is still a blank slate, or do you want it after half of the game has been played and you have felt out the other team's scheme, evaluated your own failures/successes, etc.??? I know I'd rather make decisions with a whole 1st and 2nd quarter's worth of information.
You want to score first??? See below. Listed in that spreadsheet is every Iowa conference and bowl game, in order, from 2015-2018. You can see that in 40 games, only 8 have resulted in an offensive score on the first drive. And only 3 times in those 40 games did Iowa score. Feel free to check my work.
Both teams are getting one guaranteed possession per game. Being able to use it when you might need to stop an opponent's momentum or keep your own going is huge.