The bit about preamp drive in tube amps is wrong. Think Deluxe Reverb, Super, Bassman, Twin, Tweed Deluxe, none have preamp drive.
I think the point is that beginners should try to avoid the delays and reverbs and chorus and warbles and things for a while until they understand some theory, know how to make the guitar go louder and softer without having to resort to turning any knobs (most people need to turn knobs or step on something for this), play in time, play in key, know what a key is, know some scales, know how to tune a guitar, learn to bend, learn to strum, learn to pick, learn to hold a pick, learn vibrato, learn bent vibrato (this is hard) and the other 1000 things you should know a bit about before you'll sound decent.
I mentioned pre-amp drive, but the same applies for power-amp drive as well. In my case, I couldn't get power-amp drive at non-insane volumes so...let's put it this way then: AMP drive, pre/post whatever, is not compatible with stuff like delay (or that category of effects) in front of the amp. So the suggestion of an MFX unit in front of a decent, small tube amp can work, with the caution that you understand effects loops and whether you want one.
I have disagreed with Singe on this before, and I'm disagreeing with you as well here: I don't deny that the point you're making has some validity, but that's how I started out: no effects, no nothing, just guitar and amp. And whilst I did my work getting down all the basics of fingering, picking etc. I couldn't get the tones that I wanted to get, and my playing suffered as a result because I couldn't play what I wanted to play.
Sounding decent is a combination of all the basics you've mentioned PLUS
an understanding of how to apply and control effects, the ones that relevant to you as a player. The sooner you understand how those effects colour your basic sound, the better, and the better equipped you'll be to make a decision about your next gear upgrades (which is what the thread is all about, really).