The 1980s were a strange time. 1981 was one of those where a big disparity in team mates hampered the team's WCC chances.1982 was the big one, of course, with the two prime Ferrari drivers both failing to finish the season. 1983 was another case of one driver being much better than the other. If Patrese had been anywhere near as good (or as lucky?) as Piquet, Brabham would have taken the WCC. 1986 was a good under-the-radar drive by Prost, the Williams being the better car but their drivers fought each other, and Prost did benefit from that famous bit of Mansell bad luck in the final race in Australia.
1980 - Jones won with Williams
**1981 - Piquet won but Williams won the WCC. Piquet's team mate was pretty useless - he only finished 5 races and didn't even qualify in one race.
**1982 was weird/sad - Rosberg won the WDC but Ferrari the WCC. Both Ferrari and Williams had four drivers that season, with Villeneuve dying mid season and Pironi fracturing his legs in a crash. Rosberg kind of lucked in to it a bit.
**1983 - Piquet won again and his team mate (Patrese) was back in 9th having only finishing 5 races all season. Ferrari's drivers finished 3rd and 4th, hence Ferrari took the WCC. Piquet's Brabham was probably the best car with that BMW turbo engine, but only he made the most of it.
1984 - Lauda and McLaren took the titles
1985 - Prost and McLaren
**1986 - Prost took the title with Williams taking the WCC. Again we see the title winning driver having a team mate who didn't score heavily. Mansell and Piquet took chunks out of each other allowing Prost to sneak through (thanks to cruel luck in the last race for Mansell). All a bit 2007 in some ways.
1987 - Piquet and Williams taking the spoils.
1988 - Senna and McLaren
1989 - Prost and McLaren
The 90's were of course one year where Williams won the WCC but not the WDC but they had a terrible start to the year and Hill wasn't a natural team leader in the months after Senna's death. And then in 1999, Ferrari would likely have had the WDC and WCC had Schumacher not missed several races with a broken leg Mika suffered from several retirements and Irvine probably didn't score as highly as Schumacher would have - certainly Salo coming 3rd in Italy to Irvine's 6th would make you think that Michael would have been 3rd or better there which, in Irvine's shoes, would have been enough for the title.
One thing I think looking back does show is that the reliability of the modern car is amazing - Hamilton's only had 8 retirements during his tenure at Mercedes, and three of those were in one season. He hasn't had a retirement since round 9 in 2018. That's just phenomenal and would have a made a huge difference to many a driver and team title result back in the day.