The visitors were also without a host of regulars as the match fell outside the international window, but their greater squad depth meant they lost little of their potency, especially at the scrum, where they dominated the home side.
South Africa scored 11 tries in all, as Wales crashed to the second-biggest defeat in their history behind a 96-13 loss to the Springboks in Pretoria in 1998.
Wales will point to missing players but they barely got into the Springbok 22 in a contest that must rank as one of the most one-sided between tier-1 nations as the hosts' dismal run stretched to two victories in their last 23 internationals.
"It was good, we’re proud of today and the whole tour," South Africa captain Siya Kolisi told S4C. "We’ve been building depth into the squad and still winning.
"We respected Wales as much as we could, and we needed to go out and play our game. We love the Welsh boys, I love Jac Morgan and Dewi Lake.
"We need (a strong) Wales, we went through what Wales are going through before (Rassie Erasmus arrived in) 2018."
The day was marred for South Africa for a late permanent red card for lock Eben Etzebeth, whose hand appeared to make contact with the eye of Wales’ Alex Mann as they grabbled following a stoppage.
Wales had two yellow cards as well for flanker Taine Plumtree and number eight Aaron Wainwright, though those came from pressure from the visitors, who were utterly dominant and far too physical for their hosts.
South Africa had 10 different try-scorers, while Feinberg-Mngomezulu kicked nine conversions as they ended the year with 12 wins from their 14 tests in 2025 and five wins out of five in November, sounding a warning of their potency two years out from the 2027 Rugby World Cup.
Wales are just beginning life under new coach Steve Tandy, who might have expected a big defeat given the circumstances of the game.
But it is unlikely he will have believed his side would be so easily dismantled.
"The boys are disappointed and we thought we started well, but ultimately the South Africans showed their class," Wales scrum-half Kieran Hardy said. "We just didn’t stay in the game, every opportunity we didn’t take.
"That was a tough game. There’s a lot of us that haven’t played (well) and we’re very disappointed with that."