One can operate QRP, meaning low power only, with a KX3 or a Heathkit Apache or any number of the boatanchors. It IS qrp.(low power)
The True Spirit of QRP is something very different. It is detailed in Adrian Weiss's excellent book's The History of QRP and Joy of QRP which I hasten to say many of the KX3 owner's have never read and don't care to. In his book's Adrian details this spirit which a KX3 can never bring you.
I disagree - I have read Ade Weiss - I used to read him regularly when he wrote for CQ back in the 70s and 80s, I believe. And I believe I have The History of QRP around here somewhere. I seem to remember reading about a canoe trip with a TenTec PowerMite, among others. I also have read of the backwoods exploits of W7ZOI and W6JTI and others. All of that was part of my inspiration to become a QRPer.
And plugging modules in after one has spent 8 hours putting together, an Erector Set Product like Hasbro made, is not homebrewing.
I suppose you're trying to disparage the modular Elecraft KX3 and K3 kits. I don't know of anyone who says they are homebrewing. From what I remember about Erector sets, they were probably more difficult to put together and create something neat than the KX3 I assembled. I personally don't consider the ATS-3b or MTR rigs that I built to be homebrewing either, but they involved a fair bit of soldering SMDs. The Tuna Tin 2 I built I do consider to be homebrewing, as I did it all from scratch, using Manhattan-style construction and included a keying circuit and output filter that were not in the original design. I think the filter may have been in the revision printed in the 90s (?), but I think I stole the keying circuit from some other transmitter...
It's a ploy by Elecraft to increase their profit margin giving you a 'sense' of building your radio.
Again, I don't understand why you think Elecraft shouldn't be allowed to maximize their profit! That said, I don't know that their margin is any greater on the kits than the built rigs when you consider the additional support they most likely have to provide for people who assemble their own. In my case, I welcomed the price discount in putting my own rig together - my time for that is basically without cost, as I found it an enjoyable way to spend an afternoon, playing with my new rig.
The True Spirit of QRP is the "Minimalist" approach and for other's qrp simply means low power and taking your K3 or rather qrp kx3 into the woods and operating with the finest money will buy.
"Minimalist" to me suggests something like the Pixie, or even a more complicated, but still crystal-controlled rig like a Rockmite. The KD1JV rigs are certainly not "minimalist" with their feature sets.
The KX3 is the K3 in a smaller package. So call it a qrp radio if you will. My Heathkit Apache is also qrp. She runs on 5 watts.
The K3 and KX3 are totally different architectures. The K3 comes in a 20-watt version...I would like to own one some day: it's a great rig for QRP. The K3 isn't something I would take out to a mountain-top like I do the KX3...but it would be a super home-station rig.
A rig that runs 100 watts isn't what I would consider a QRP rig, but yes, you probably can run at 5 watts output with it.
I feel no shame in operating any of my QRP rigs, but I do not consider myself a minimalist, nor do I consider that a requirement to be a "True QRPer".