The 2N3819 is very old for sure. I've been using them since I was a student but they date back way before then.
However, the real point of showing the oscillator circuit was to demonstrate that JFETs (and BJTs) can become oscillators even when the circuit doesn't look like an oscillator at first glance. When this happens, it is often best to analyse the circuit as a 1 port device and look for signs of negative resistance
I chose that topology because it's the easiest to analyse and it's possible to predict the amount of negative resistance and the oscillation frequency based on the datasheet 'typical' figures with just a few simple calculations. No need for a simulator or a VNA. Obviously, a real JFET will have differences in Cdg and gm etc and this will affect the amount of negative resistance and the oscillation frequency a bit. But I'm not sure that's relevant if we are more interested in the mechanism that causes the negative resistance in the first place. The modern ON Semi datasheet for the 2N3819 has s parameter measurements up to 900MHz and the gm holds good up past 500MHz and only really fades badly towards 900MHz. I've not tried to get a 2N3819 to oscillate at 1GHz but I think I could get fairly close...
Other JFET configurations like the (source follower) JFET probes can also generate negative resistance and this is less obvious and it's a bit harder to calculate how much will be generated. The Bob Pease JFET active probe looks to me like it will generate a lot of negative resistance at its input across upper HF and into VHF for example. The Marconi TK 2374 200MHz (JFET) RF probe looks to combat its own negative resistance with a series 100R resistor near the probe tip.