Ok, from one point of view it can be good that LFS would have compatibility with older systems, run smoothly on Pentium 4 with 1GB RAM. But that way you will never achieve more accurate simulation and better look & feel.
By FINALLY moving step forward you can get better physics by using multicore/threading opportunity, much better graphics with today's GPU. That way, you will probably loose some of players with 10yo computers, but you can get many new players with modern PCs who are waiting for simulators of 2012 like rFactor 2...that could be another LFS...
imho it's silly to provide backwards compatibility for such old systems. The sooner jump to multi-core universe, the better.