You have systematically excluded Philander, Rabada, Pollock and every other great pacer Steyn played with and are arguing, wrongly, about the rest of 27 tests (15 played with Ntini-Morkel and 12 Morkel). By definition, your initial claim was incredibly wrong and that you have absolutely no desire to look honestly into what you write speaks to the cancerous blob your posting has become.
I haven't excluded Philander at all, but he only played 40 of the 93 tests Steyn played. Pollock played 9. So that's half the tests Steyn played. That's still leaving the other half of the tests he played between around 2008 and 2012ish where he was taking loads of wickets without much support.
And South Africa is definitely favourable conditions for pace bowling, generally speaking, so arguing that guys who averaged around 30 playing half their tests in SA constitute "good support" is petty ordinary.
Let me ask you this. If you took Steyn out of the South African attack before Philander emerged, would you have thought their attack was good, or at least had a decent threat? After Pollock's retirement I don't see how that could be argued. Morkel's length was rubbish, Ntini was nowhere near as good as he was around 2005 and the other guys on the scene were players like Nell. Aggressive but not exactly world beaters. It wasn't Hadlee- support level bad, but as far as South African pace attacks go out was easily the worst few years since readmission.
It's part of what made Steyn so great - he was demolishing sides when nobody else was anywhere near his level worldwide.
I mean saying that Murali had rubbish at the other end is an overstatement too since he had Vaas and then Herath but the overall quality of the attack sans Murali for much of that time was Zimbabwe 2003 level - one test level bowler and then some fodder.
In virtually every great bowler's career they'll have at least someone half decent at the other end. Hell, even Hadlee had Chatfield. But Ambrose never got the high wpm values because he was competing with Walsh and Bishop. McGrath competed with Warne. Holding with Marshall and Garner. Donald with Pollock and de Villiers.