I'm afraid you've missed the whole point of what I wrote earlier:
keep in mind that big brands tend to be people's favorite brands [...] Google has nothing to gain from promoting specific brands other than that it's what their users want to find, and [that] helps them.
How many people do you think searched specifically for the brand name of your small business vs. BMW?
In other words, how much of an effect did your penalty have on Google's users vs. BMW's penalty?
Any time a major brand goes missing from the search results, that's a problem for Google. Not because the big brand will get angry with them, but because a significant number of their users are negatively affected. Particularly when it comes to popular so-called navigational queries like "Facebook" or "BMW" or "Amazon", where people are just using Google to "navigate" to those websites, as opposed to more general queries where different brands compete like "electric sedan" or "toys", i.e. where users' queries can still be satisfied by other brands.
Still, of course BMW had to be penalized until they were no longer in violation. You can't have double standards there.
Lifting the penalty of BMW much faster than that of your small business was not a double standard, it was a matter of priorities; every day that the BMW website could not be found, many users were having a poor experience, so it made sense for Google to act quickly. A small business affected by a similar penalty, on the other hand, would probably be part of the long tail of penalized sites that individually just don't have as much of an impact on Google's users. This was 16 years ago and they eventually did away with the reinclusion requests, presumably because they obviously didn't scale very well.
When you accuse Google of "prostituting for big brands", you're suggesting that big brands essentially control Google, and so missing or ignoring a very important piece of the puzzle: Google's primary focus is on pleasing their users. The users don't know it, but collectively they are in control. Google doesn't care about big brands because they're big brands, they care about big brands because, as I wrote earlier, "big brands tend to be people's favorite brands".
Big brands don't steer Google, users do. It's an important distinction that I hope you'll keep in mind.
Of course, brands do influence those users, but that's a different matter.
