WOW! The first bass I ever had in the mid to late '70's was a red 3/4 oriental P-copy with a multi-laminate neck and a small bar pickup that had these nylon sleeved strings. I bought it from a friend for $100. Fender made them. I'm really showing my age now. Yes, thumpy is an understatement: all thump, no sustain, all of the time. But that was the tone of the day, especially with a pick: http://musicmansteve.com/parts/gp062.htm
I liked his bass. I wasn't sure he would sell it; he wasn't sure he would sell it; I wasn't sure I had the cash. So we made a deal: at the end of that week at school, if he wanted to do the deal, he would bring the bass to school. I would bring a $100 bill. If either of us didn't bring it, the deal was off. On Friday morning, we both walked into the lobby of the high school at the same time. He had a bass case in hand, I had the $100 bill in hand, and we did the deal. I took the bass to the band room and put it in the band closet for the rest of the day.
Yes, especially in short scale, those strings were all thump, all the time; but at that point there wasn't the wide range of strings available as now.