The "ancient" 3.3L in my Highlander is a pretty nice engine! It's somewhat down on power compared to newer designs (230 vs 270hp) but still delivers solid fuel economy (11-12L/100km in all city driving in a 3900lb AWD SUV is very acceptable), is so smooth you have to look at the tach to see if it's running, and judging by HL owners with way more kms than me, long lived. Yeah, it has a timing belt than needs swapping every 150K, but it's not a tough job (nothing compared to the Subaru) and since you might have only two in the life of the vehicle, not really a consideration in the long term.
I suppose if I bought new and traded every few years I'd be more concerned about having the absolute latest and greatest, but personally I'd rather have tried and true. I got burned a bit by the Germans by buying leading edge technology, and today I'd rather have something I know will just get the job done.
One thing to note about the various Toyota V-6's I've had the pleasure of driving is that power delivery makes a big difference in how they feel. They make power down low, meaning access to grunt right away. The VVT-i systems have a "v-tech kicked in yo" effect, but the immediate delivery of thrust is very noticeable.
As for BMW and Mercedes, I miss the great I-6 engines they dropped into the cars forever. Those old single cam 3.0L engines Mercedes used in the original 300E and 300SE/L were not powerful like a modern engine (177hp from 3L) but they sounded nice, were smoother than most V-8s, and lasted literally forever with regular oil changes. They needed almost no maintenance and when they did, were super easy to work on. A new timing chain was needed usually at about 300K and could be installed for less than the timing belt on most cars. Plugs sat on top, could be swapped in a half hour including time for a beer. I owned a 190E with the 2.6L version of that engine and it finally left our home with 510,000km on the odo and the engine and trans had never been opened.
In many ways, modern Toyota engines feel to me like those old MB and BMW engines. Built solid and made to last and last. The article rr posted about the modded 2.5L I-4 engine blew me away with the thought that's gone into a "plebeian" four banger that's used in the RAV. In stock form, that thing is way over-built for the modest output. Toyota might be cutting corners in a few areas like interior materials to stay price competitive, but it seems to me that the engineering goodness in the mechanical systems is not only still there, but in many ways still at the front of the pack.