This advice holds up, but there are caveats to keep in mind. Two off the top of my head:

1. I once worked for a company that had a large Cassandra cluster that was primarily serving the role of a distributed append-only log. This role is as perfect a fit for Cassandra as I can imagine. When we needed a distributed database for authentication, we decided to use Cassandra for it since we had in-house expertise (it was "boring technology") and a cluster we could piggy-back on for a while. When we needed a distributed database for a key-value service, we used the same reasoning and chose Cassandra again. There were many problems with Cassandra that I won't go into, but I will say that straying too far from Cassandra's comfort zone stretched it to a breaking point. And we had some downtime and rough nights because of it. Sometimes boring technology isn't enough, you also need boring workloads for it.

2. I was an early adopter for Rust. Before 1.0, it wasn't clear to most people whether the language would mount to anything. To me, I saw a formal proof assistant being put into programmer's hands and could tell right away it had a bright future. Rust was not a boring technology back then. You might say it is now (for some use cases). Adopting shiny new technologies that measurably improve confidence is not a risk. What's foolish is getting comfortable and complacent with familiar, aka boring, technologies that are difficult to use correctly.