Here’s my opinion and why I did it!
I owned three diesels( 89-7.3 idi , 11-6.7 and a 15-6.7) I now own the 7.3 gas. I use my trucks for work and they make me money. With that said I would agree that the diesel resale is higher as well as the upgrade itself. The diesel cost more or less about $8500 more than the gas 7.3. Mileage, the diesel is better but fuel Cost is more than gas to offset the difference in mileage.
I have a slide in body for my work and weights about 2000-2500lbs. I do not tow much at all. So for my needs the gas suits me fine. The diesels were very good to me but much more maintenance than the gas version. I never kept either 6.7 past 60k but also glad to not have any of the major issues that these can sometimes have.
The gas gives me peace of mind and I love how it sounds!
2001 F250 7.3 200K no issues other than starter and cam position sensors (spare truck)
2013 F350 6.7. 180K with no issues
2014 F250 6.2 gasser 160K replaced exhaust manifold otherwise stock (currently a spare truck but everyone takes the '01 7.3..)
2018 F350 6.7 34K (my personal truck)
2019 RAM 3500 6.7 10K (needed bonus depreciation and couldn't find a F350 spec'd right and decided to give RAM a shot)
The Ford 6.7's have been bullet proof and very powerful - I'd buy one again in a heartbeat. The Ford 6.2 gas sucks compared to the 6.7 and never care to own one again.
As Bullitt said the premium for a 6.7 is around $8500 which is well worth it IMOP and one gets it back on resale.
I went back to gas, due to not hauling as much, and as often as I did with my 6 leaker. This truck is my family/weekend truck. I also figure it is less maintenance and fuel cost . I normally can't leave well enough alone, so I figure Procharger will have something out soon enough. I do miss my diesel, but I will adjust fine.