Part of Basecamp's schtick is to rail against tech monoliths and borderline ethical business practices. He uses words like "shakedown" and "ransom" to elevate the seriousness of the situation. Readers must understand this was an intentional grab for attention — and an extremely effective one at that. If you want to get noticed, be polarizing, stand a stand, have an opinion, choose sides.
But don't be fooled: it's a test to see if buying branded search keywords are actually effective. He's asking users to search "Basecamp" and see if it actually tangibly results in something. It's a twofer... viral marketing and search marketing.
Now to get to the actual Google Ad... Google Ads are text-only, making copywriting the ultimate factor for success. The results are unknown, but the execution is flawless. It's purely a play for brand affinity.
Notice that there's isn't actually a call to action. Instead, it's almost reverse psychology. "We don't want to run this ad." = "Don't click this ad." = "Click this ad."
Instead of describing what Basecamp is, they describe *who* Basecamp is. They're a fish swimming upstream. David facing Goliath. Small but mighty.
Google Ads are largely commoditized across the web. Most follow suite to look and sound nearly identically. This is a great example of how zigging when others zag can help you stand apart from the crowd.