I'll throw my hat full of experiences into the ring. I grew up in a die hard Ford Family, dad and grandpa both still drive early 2000's low mileage Power Stroke 1 Ton's (dad's has about 120k on the 7.3 and his dad's has about 125, so yes actual low miles). They've held up great and dad's big truck has always been blue oval.
When I graduated college and got a real job in June of 2019, I dumped my Corolla that I drove in college and bought a 2015 3.5 EB with 63k on the clock. It was NICE. It was an XLT package, but it had been dolled up significantly. Crew Cab short box, firestone airbag system, leveling kit, bead lock rims, 10 ply tires, dark window tint, it was clean. I picked it up for 28k and was excited to have a low mileage, reliable, clean title vehicle that I could keep for 10 plus years and own it for awhile. I took it home happy and proud of my purchase. Look at me being a grown up!
About a week later I noticed some oil drips on the concrete underneath. Crawled underneath and it had developed a front timing cover leak. I took it back to the dealer and they had it for a week and got it back to me, good as new (I thought).
3 Weeks later I heard the timing chain rattle for the first time (google it, you'll find thousands of videos depicting what I'm talking about).
I took it hunting and towed a single side by side on a small 14 foot flatbed trailer, darn thing got about 4.5 MPG down the freeway. Granted, I had the cruise set at 80 and was running away from my dad towing the jeep, but come on, 4.5 MPG?!?
While on the mountain, the timing chain rattled EVERY MORNING. At this point, the truck had about 65k on it, and it had only ever been driven back and forth to work in my home town and on the occasional date with my wife. I hadn't towed with it AT ALL when my dad and I went hunting. It hadn't gotten hot, but it did it every day. This was in September.
I took it home after the hunt and started to have some serious buyers' remorse. I had a sinking feeling about the truck, but I couldn't figure out why.
Late October, at 65.5k, the transmission slipped while pulling into traffic onto our local main street. I didn't think much of it, but then it started to happen consistently. In early December, a factory reman'd trans unit was installed to the tune of $6k. Lucky me!
3 Days later, check engine light pops on for a random cylinder misfire. Plugs and coils on all 6 cylinders at $175 each, this truck was getting expensive. Plus I still had that random pesky timing chain rattle.
I decide to dump it and get out of it, and stick it on the local classifieds and start looking for something else. I also started to look into trading it off. I had put over half the money down, so I had good equity and probably wasn't gonna take a huge loss on it. I took it to a dealership who, long story short, toasted the new trans doing brake stands behind the dealership to "check if the trans was reman'd properly." Needless to say, Dastrup Auto in Lindon Utah wrecked the trans.
I ended up trading it in on a 2013 GMC Sierra half ton extended cab. The dealership chain I worked with has many connections to get stuff fixed (huge network of ford, GM, Chev, Ram, Dodge, etc. dealers all together), so they basically said they would ignore the trans and timing chain issues and ended up giving me 25k on trade for it. After the deal was done, they pulled up the Ford work log that tracks repairs done at Ford Authorized facilities. Come to find out that, in 68k total miles since that truck was built in 2015, it had had the following fixed:
1. rebuilt rear end
2. 2 sets of turbos
3. timing chains/cam phasers
4. rebuilt transfer case
5. 1 trans prior to me
6. coolant leaking into combustion chamber
7. plus all my stuff
The lead tech at the shop looked through the list and said "yup, sounds about right for the Ecoboosts. That's what most of them look like that come through our shop." I was dumbfounded.
My dad drives a 2019 with 38k on it and has the timing chain rattle, and just had the trans rebuilt. He drive about 25k a year for work as a salesman and has NEVER towed with it. His company pays for gas so he drives a truck just because.
I now drive a GMC and dad is looking to sell his 7.3 and buy a Duramax. Lots of pattern failures on the Ecoboosts and 5.0's (timing chains and tensioners, cylinders wearing out of round by 100k), and even the new 6.7 power strokes have their share of serious problems. Ford just is not the same company as it was 25 years ago. It's sad to admit as a lifetime Ford man, but we've been burned for sure...
Bottom line, buy with caution.
EDIT: I have an uncle who is a performance gear head and knows how to maintain, work on, and fix vehicles (drove his old 24 valve cummins to just over 800k). He has a landscape business and an oilfield business, and has a whole fleet of trucks, most of them gassers (except for his personal trucks and a couple of his superintendents, they all drive diesels). When I asked him about the Ecoboosts, his words were "they're awesome if you drive them empty. But at the end of the day, you're taking the same size engine as a Honda v6, putting 2 turbos on it, and asking it to do the same work as a V8 in a truck. Would you put your mom's Honda Pilot engine in a truck?" That was kindof the final decision maker for me.