I have both tripods and monopods - The tripod is a Manfrotto and weighs as much as a small child - it almost never gets used - I bought it cheaply due to a casting fault (which I repaired with an aluminium frame milled from a single piece.). As to normal movie-filming I use a monopod - not the commercial ones - mine extends to 10ft or more and has the huge advantage I can have the camcorder as low as 12" off the ground. It provides a high view-point so you can be above walk-on folk - as well as cars.
I don't think you can buy such a Monopod-spec and I'd be wary of the inexpensive tripods that boast a central monopod - I had one that reached 70" (I think), but the monopod was quite short of this. Also being a four-section tripod, the smallest leg-extension was very feeble. I don't have it now as the plastic collar that supported the leg-splay snapped. It was a design that could have been improved - I had to "Silence" the pan-handle ( as it was rattled in the head )- brass shim fixed that, but few folk would be able to make any "improvements" without a home-workshop. One reason for buying the convertible tripod was to remove the centre column and install a jib for those "Sweeping" shots. It was returned before it was operational. It worked for this task as a 3-section tripod. I wrote to the manufacturers but it's difficult to find who is the maker... and who is selling-on - it needed 4" longer leg-sections and drop the fourth.
Covid has stopped all movie-activity, although I have an idea for a monopod with an 18" arm (Provides nearly 3ft movement, I hope). When closed my monopod is about 5' long so it can be taken on the train, carried about, etc. I never understand why tripods/monopods are the height they are - harking back to field-camera days.... IMHO any camcorder support needs to be 6ft or more to get over the heads of crowds.
Mine, having such greater "reach" was useful at an agricultural show where bales of hay were being thrown onto a haycart. - I was able to film from stacking-height . . . . it surprising how much smaller farmhands on the ground appear. A few seconds as a "Cutaway" really is the "money-shot" - something I've repeated (with permission), float-close at pond-fishing . . . . without leaving the bank.
Another good use was filming soldiers on horseback, where my camcorder is at rider height.
At steam Fairs, a high-shot of the Engine+Crew is so much better than being rooted to tripod-levels.
BUT the choice of tri-/-mono should depend on your filming activity.
Yet, somehow a tripod does appear to be more popular.
Hope that helps.
Cheers H