I think this is one of the fundamental quandaries of many services that sell to developers. There's always a way to roll it yourself such that the cost in money is low but the cost in time is high.

For me, I just don't have enough time in the day (parenthood + day job as an investor) so when I do code, I am looking for a lot of leverage, and I'm willing to trade off a monthly fee for it since it's like licensing software that lets me get something done a lot faster.

Most cloud services are like this: You could do it yourself, but when you compare it to hiring more people on your team, you should use a cloud service.

The upside to this is that a lot of startups are going to be able to get a lot more leverage through building on top of services like Algolia. I mean, this is really the AWS strategy in a nutshell, isn't it?

I would agree on your point here, in some ways. Algolia is a limited search; there's a lot of things you can't do on the fly (that you can in, say, SOLR). However, the onboarding (as noted) is pretty good. It's really easy to get started using it. The learning curve is much lower and so, too, are the capabilities. If you don't need those extra capabilities, you just need to get search available, it might be the right thing.