This isn't true at all. The ES/RX series of Lexuses have some very serious engine and transmission concerns, the transmission in the AWD RX300 seems fairly weak and I've heard some problems in the ES line but not as many. These cars also have a serious engine gelling problem up until about 2002 unless the oil was changed according to the severe maintenance schedule. Lexus also has problems with their gauges in older models needing to be repaired, the first gen LS and SC have a bad power steering leakage problem and a stupid design that causes the leaking pump to fould alternators. There are also significant problems with the LCD screens in the dash that can be very expensive.
No car line is perfect, all in all Lexus is a fantastic car but to say there is no such thing as a weak component in these cars is pure fantasy.
Monarch and some others will tell you about huge hundreds of thousands of miles of life of specific performance out of certain components. Bear in mind those are PAPER figures and don't translate into reality like they assume they do. For instance Monarch's quote of 400k for an A/C compressor is rediculous, it depends on how often its used, the climate. My dad had one AC compressor go on his LS at about 80k miles.
American cars, while on average are definately less reliable than a Lexus or Toyota are not accross the board garbage. I know people with hundreds of k on Saturns and they're fine. Monarch's mom's Saturn, 14 years old and 38k miles? Come on Monarch be straight with the guy, that thing site 95% of the time and thats whats leading to component failures. You know as well as I do that sometimes driving a car is better for it than not driving.
Its not as cut and dried as some people would like to convince you it is.