That would be incorrect as their software was more solid than any of the other junk out there at the time for many years. If SQA is an innovation, they did a decent job of it considering the size, scope and breadth of all their product lines.
Having been a former Lotus engineer I could give you some major insights into why MS killed them off as I was there at ground zero watching it happen. It was a lot of internal politics, poor engineering and the arrogance of Lotus thinking they had a lock on the spreadsheet market that would accept their sub par products such as the fist 1-2-3 release on Windows which was their undoing. The MS Excel product by comparison was far superior and had absolutely nothing to do with MS owning windows, it was the engine that ran 1-2-3 that was too slow, all internal software, all Lotus, all crap.
Same thing happened to WordStar and then WordPerfect and of course Lotus' AmiPro, all had the same fate.
However, you can look at companies like MacroMedia and Adobe, now the same company, which never dropped the ball, never sat and whined about MS, they just kept rolling out superior products year after year.
MS raised the bar and those companies that could meet the challenge are still doing well and those that couldn't are footnotes in Wikipedia articles.
Bill Gates was very shrewd and will be sorely missed in this industry.