Modern pulse MIG has only one advantage over the 25year old pulse MIG, it is a LOT better on thin aluminium, other than that, ill take the 25 year Esab over our brand new Kemppi or Migatronics any day, it just welds much nicer.
As for TIG, i would say modern machines are better, but not for the functions, but for the stability in the arc.
I personally dont use anything besides up and down slope and postflow. And of course 4-stroke (you call it that in english), so pretty much any machine from the last 30 years have the functions, but any machine shure as hell dont weld nice.
The real big difference to me is in AC TIG, where only a few brands make really good machines. Migatronic is IMO far superior.