People are still building "tuners", they are just not going to the traditional shows. From my own experience in the 90's when the sport compact scene was picking up, people who brought their import models to the shows got lumped into whatever group that was not rod, custom or muscle car. Usually it meant lowriders and slammers. Most showgoers were indifferent to them and some sneered at them about "Jap C*ap" or "cram a V8 into it". There was no chance for them to win, no matter how well they were built, because they were in the wrong category. It got off-putting enough that they stopped going to the shows and formed their own groups, and it stayed that way.
So I think it is nice for people like Tom to bridge the gap between the two groups, to bring more modellers together despite the different genre they build in.
As for tuners being a fad that went out, yes the copied Veilside bodykits and scissor doors are out, but they are only a very small subgroup. Less people in North America are tuning Honda than before, but that's because Honda hadn't sold anything sporty and affordable since 2003. Their place have been taken over by Golf GTI and Mazda 3 and WRX, and soon the FR-S and Focus/Fiesta ST. While the stereotypical "tuner" has faded out, the actual scene is going very strong.