Alta Vista started out with a modest size index of 20 million pages. Let's imagine those pages were all of 1Kb in size, then, 20 10^6 10^3 comes to 20 *10^9 or 20Gb. So, in terms of stuff indexed, that is considerably larger than TPB. Agreed?
Well, maybe not. They could have used compression to get the vastness of TPB onto that USB stick. Around that time - 2012 - they had 1.6 million torrents. That is some way off the Gb that AltaVista indexed, no matter how you bloat the maths. Sad to say, but, in the 1990's, the internet was actually larger than your porn collection.
How useful is reqs/second anyway? By that score Google probably does very badly as a search usually returns the answer on the first page. With old-style search engines you might need to go through scores of pages before getting what you want. I found TPB to be a bit like that too, wading through results pages more than necessary.
TPB is not 'safe for work' and in a lot of jurisdictions you cannot even access it from home. In the UK (which is a small but well populated country) it is not that easy to get onto TPB - you have to have hacker voodoo skills to do that or route through a VPN as none of the main ISPs will let you on. Most of the civilised world has the same need to protect citizens from the evils of TPB so places where it can be accessed are not that common. Even if you could access it, would you? Probably...
Meanwhile, back in 1998 - a year or two before the dotcom crash - plenty of people were using search engines such as AltaVista (which was the best back then) for actual work. Maybe not everyone, but enough people knew about computers and things like AOL disks, modems and what not. The internet was big.
Which reminds me of my main point, the one you thought so important to down vote rather than give kudos for being insightful. TPB uses a constellation of computers and consumes vastly more resources than the biggest search engine of the 1990's, yet, the utility of TPB is limited to only a few fortunate enough to live somewhere where TPB can be accessed. What can be searched for on TPB is a mere subset of what was on Altavista albeit different and not so useful stuff. I would say that with AltaVista they were doing far more with what they had, reaching a better audience, doing something more useful for the world (than serving weight loss adverts) and all together performing a miracle. TPB is a slouch in comparison.