Well, it sounds like you had an oddball race though (meaning you had to make an unscheduled stop torward the end of the race), forcing you to run a comprimised strategy...making the scenario a bit skewed to say the least. Also, in reality it's preety much impossible to calculate what making that extra stop cost you in the end, because there are variables that never took place (like what your pace would have actually been had you not made an extra stop, and what you could have done had you planned a 2 stopper from the get go), and all we have to base things on are assumptions (which generally aren't that accurate over a period of 10-15 laps) of what kept your from getting a 4th place and bunch more points, which was ~ only 6 seconds down the road at the end of the race.
So who knows, maybe if you had decided on a 2 (assuming that's what you did?) stopper from the beggining you could have placed better than you did, because you would have been able to maximizes the tires better throughout the race, while still having the potential to really hammer out the laps early in the stints to try and bag that FL 💡
It's really all scenario based though, depending on the track/each cars tires wear characterstics/ how much ballast you're loaded up with/ and a drivers ability to run long stints while maintainingg the strongest pace possible. In some races where your only realistic/practical option is say a two stopper, than it's certainly not going to be wise/or make sense to go for a 3 stopper to try and snag a fastest lap, as you'll be set back to far in terms of on track position torward the end. On the other hand, when we run into scenarios where say a 1 or 2 stopper is a viable option (with no real clear benefit in terms of the results in the end), then it would more than likely be wise for people (particularly the fastest drivers) to just go for the same strategy to try and get that fastest lap, which can make all the difference when it comes to who wins the Championship. But in the end I shouldn't be making such a big deal of this I guess...as there are already so many variables in the Championship (between the cars, how ballast affects the different cars, tire wear, etc.) ...this issue is rather minascule in the big picture.
And I hate to sound redundent, but if we're going to place such importance/weight on the fastest lap...then so be it. I guess I'll just have to play my cards so that it benefits me the most...