So are dynatron oscillators just lost to time? And if so what does this mean for other tech?

I was thinking about how vacuum tubes not matter how obsolete will always have some use as the cool old fashion guys but then I realized that some tubes are just gone. Like are there any surviving dynatrons? Are dynatron oscillators just impossible to make now? Are there other things like this? Crystodynes aren’t only saved from this because anyone can make them but dynatrons are like specialty parts that require big machine to produce, and it’s not like Nixie tubes where people really like the look of dynatrons. It’s kinda like tetrode transistors but if they were cool, and not tetrode transistors( yes I know tetrode transistors still exist but who cares about them) or like the original idea of a magnetron being a magnetically controlled vacuum tube. Are all the neat little components just going to die out one day unless some audiophile says it’s actually the greatest thing ever?