You're ignoring that building Craigslist was as possible in 1995 as building its replacement(s) is now. Disrupting the global print classifieds market in 1995 using an unfamiliar new technology was hard, and companies aiming to disrupt CL now will have to work at least as hard (and possibly ride a wave).
In fact, the major difference between 1995 and now is that CL has concentrated the market from zillions of local print publications to a single website. That means they are more vulnerable in some ways than "print classifieds" were in 1995. (It also means they have to stay on their toes to make sure they keep their users happy.)
>> It's now virtually impossible.
Air BnB shows that it can be done, so we know that it's not impossible to build a challenger. And we knew that it would be virtually impossible, or everyone would do it.
In fact, the major difference between 1995 and now is that CL has concentrated the market from zillions of local print publications to a single website. That means they are more vulnerable in some ways than "print classifieds" were in 1995. (It also means they have to stay on their toes to make sure they keep their users happy.)
>> It's now virtually impossible.
Air BnB shows that it can be done, so we know that it's not impossible to build a challenger. And we knew that it would be virtually impossible, or everyone would do it.