Depends on one's definition of 'boondocking', it has been many years since we have done in the boonies dry camping. But for dry camping, most times it is how we camp/overnight and/or stay.
If you would count dry camping in a somewhat undeveloped place to camp, but with a fee to use, we did several nights & days at one across Resurrection Bay from the town of Seward, Alaska starting 20th July. $15 a night, on set site markings, large gravel graded area, no tables, no water, no developed fire rings (a few made by earlier campers), no real shade (a tree line between some of the 'parking/camping' area & the beach), but two outhouse toilets & dumpsters.

We also dry camped at Morgan State Park near Soldotna, AK (had fire rings, grills, tables & gravel site, road) & at Clam Gulch State Recreation Area (gravel parking lot site (no fire ring, grill or table at our site, which were numbered/marked. Then we went back to the Seward site for a few more days. Seems they were about $10 or $15 per night as well.
We where in a rented Aliner towed with our son's TC.
For last time dry camping in the Lower 48 in our Scamp, this would have to be at
Juniper Camp Ground at Bandelier Nat'l Mon't (3 loops, 56 sites, I believe). $6 a night with Senior Pass. Stayed two nights. No electric, first come, first served, water near by in campground & at the dump station. Nice campground. Flush toilets, no showers. One may run generator from 8 am to 8 pm if needed. This is in the 47th State, New Mexico - With A Trip Report last summer.

As for real boondocking: Did a few trips dispersed/boondock camping by Cloudcroft, NM years ago in the Lincoln Nat'l Forest.
:S As for some real remote boondocking: The
Springtime Campground (but only 12 miles south of I-25 exit #115 via NM 1, FR 225; we always used the Red Rock Exit 100, then NM 1 N to FM 225) and the
Luna Park Campground (only 8 miles northeast of Monticello via FRs 139 & 225, but we used CoRd 34 from exit 92 off I-25) always seemed pretty remote. In Southern New Mexico between Socorro & Truth or Consequences (TorC).
I have driven by Spring Time & Luna Park with a Scout II & a CJ-7; I tent camped dispersed near Luna Park (off the road over some hills in a saddle between two hills (must have been the most true boondocking we have done, 33 years ago. On the road to Spring Time, we dispersed in a Class C MH.
Never camped here,
Red Cloud Campground (18 miles southwest of Corona via US 54 and FRs 161 & 399 Latitude: 34.2103491 Longitude: -105.7558336) seemed pretty remote as well when we drove by Red Cloud in a Ford Ranger deer hunting some years ago.
In the Gila Nat'l Forest (on the edge of the Gila Wilderness),
Dipping Vat Campground is adjacent to the west side of Snow Lake. Snow Lake is approximately 52 miles southeast of Reserve, New Mexico.
Willow Creek Campground is near by as well; approximately 55 miles from the town of Reserve. But from over by Glenwood, from US 180 to Mogollon on NM 159, then FR 142 & FM 1421, it is only about 36 miles. Maybe a little less than two hours to drive.
I have camped at Willow Creek in a small TC. I drove over to Snow Lake in a small TC, really a camper shell, no over the cab. Almost 40 yrs. or so ago.