You can´t really compare them both since they're more than 20 years apart. Those cars, like Hannu Mikkola says in the beginning of the video that Zeug posted, could drive around a track close do the times F1 cars did back then. Don´t think we could say the same about modern WRC. Those cars were just too fast, too powerful, too dangerous and too demanding for the drivers, and because of that, they were banned. And the way the public felt about rally at that time was just pure madness. Nothing comparable to what we have today...
Same here... Seeing them live is an experience that I don´t believe any motorsport fan could forget...
Like people have said it's not the absolute speed the cars go through the stages. It's the style and the effort the drivers had to put into finishing a rally.
WRC events these days are very short compared to the events they ran in the mid 80's. The ~300 special stage kilometres they do over the weekend these days were often ran during a single day! Events lasting three, four or even more days were simply exhausting.
And then there are the cars. Active differentials, improvements in tire and suspension technologies (and also aerodynamics if you compare group A homologations to WRC models) have made the cars go through the stages like on rails. Smarter engine design and clever engine management systems mean that the cars output usable torque through a wider rev range and therefore don't sound that nice anymore
Group B was the king, although the specialiced cars can put some off. The group A cars of early 90's were spectacular as well.