I do not really agree with this, just from my standpoint. Before I started almost 2 years ago I read so many posts (from many areas), watched videos, and browsed a few books.
The first thing I did was look at what I already had on hand. 30 qt turkey fryer, small dorm fridge for temp control, that's about it. I did not buy a kit because my little fridge could not handle 5G bucket/carboy. However a 4G square bucket with an airlock just clears. Then just bought items needed, for cleaning, bottling, etc.
So this left out any chance of brewing 5G kits. And when I started looking at the costs for extract vs all grain, this was easy - all grain. Now which way was I to go, easy BIAB, because it was by far the easiest way to do all grain, paint strainer bag good to go.
Now after almost 2 years I still use same burner, fryer, and fridge. Bought a better bag (wilserbag)

and use a stainless hop filter and never started with extract.
Now granted the first couple brew sessions were not the best because having to learn the system and procedures, but if I had to do it over again I still would go straight to BIAB.