At ~9:50 Michael Moritz talks how the 100-year media history tells us that if you can gather a large audience in one place, you will be able to sell them advertising.

It's likely that Google will not be the last search company. What business model could a successor use to generate revenue without falling into the ad trap? Why didn't early search engines choose other models like subscription, revenue sharing with telecom companies, or turning queries into marketing signals for manufacturers/merchandisers?