I've played the Star Wars games a couple of times - they really are quite good.
Disclaimer for the below: I am/was an unabashed GW fanboi for many years, so maybe I'm looking at it through rose-colored glasses.
GW rose to prominence primarily on the strength of their Citadel Miniatures branch. Anyone with hair as gray as mine remembers the shitty state of fantasy/sci-fi miniatures back in the 80s -- back then we honestly thought the Ral Partha miniatures line was high art.
OK, to be fair, a lot of the Ral Partha figs were pretty great. But the Citadel stuff just blew them away in terms of detail, dynamic poses and overall fantasy design. I was working as a clerk in the local hobby shop in the mid-80s and the Citadel stuff out-sold every other line by some ridiculous margin.
Despite the figures boosting the games, I'll argue against the sentiment that GW's game-design skills are lacking.
As Panzah notes up-thread, there wasn't much competition in the tabletop fantasy miniature arena. I mean sure, there was Chainmail. And there were a few historical miniatures games that could conceivably be converted to use elves and dwarves and whatnot (e.g., DBA), but most of these were ludicrously crude. Hell, when the original WHFB came out in the mid 80s, Dragon Magazine lauded it for being so sophisticated.
So yeah, the genre has matured in the last thirty years. But remember also that GW put out a lot of other - mechanically much better - games alongside the WHFB and WH40K money-machines.
Space Hulk is a great board game. Talisman is really good. HeroQuest, Battle Masters, Blood Bowl, Warmaster, etc. are all pretty good, even without the figures.
And as long as we're talking about the Star Wars miniatures game: For my money, one of GW's best games was Man O' War, a sailing ship combat game set in the WHFB universe. The expansions largely ruined it, but the core game-play was fantastic. The movement and combat rules of the SW game owe a lot to MoW.