*Knowledge, definitely.
*Luck, less so. There are many clear quant signals that have persisted since the 1940s. Core principles like "value" and "momentum", when executed well (and in tandemthey work better together than in isolation, as doing so helps avoid value traps and over-hyped alleged growth stocks), can beat the market. The beauty of quant systems is they help investors avoid the psychological pitfalls that often translate into money-losing behavior. There's variance, sure, but I wouldn't call that pure luck.
*Money, I'd argue, cuts both ways and can actually be something of a liability. One of the reasons asset managers often struggle is that with substantial assets under management, the pool of investable companies is dramatically smaller for liquidity reasons. A savvy small (i.e., <$5M) investor can move nimbly into and out of some of these positions without major slippage. Where more money helps is in being able to afford risk control tools, since the good ones tend to start at $100K/year or so.
The fact remains that the vast majority of professional money managers don't beat the market over time. A year or two here or there, if they are really good, but even then not often or consistently enough to justify their existence.