JavaScript’s Date object has spent decades making ordinary time handling feel more dangerous than it should. It is mutable, mixes several ideas into one type, and makes timezone mistakes remarkably easy. Libraries filled the gap because they had to. Node.js 26 enabling Temporal by default is therefore much more than a tidy API addition.
The Node.js 26 release announcement lists Temporal as a headline change. Instead of treating every value as a variation of one awkward object, Temporal has distinct types for instants, calendar dates, times, durations, and zoned date-times. The names are longer, but the intent is much clearer, and explicit intent is exactly what date code needs.
I would not rewrite stable production date handling just to use the newest thing, especially while Node 26 remains the Current line before entering LTS in October. I would start testing dependencies and use Temporal for new code where the deployment target is controlled. For libraries or applications supporting older runtimes, a compatibility plan is still needed rather than assuming the global API exists everywhere.
The important bit is that new JavaScript can finally begin from a better default. Dates and timezones will never be simple, because the real world is not simple. At least the standard runtime can now represent that complexity directly instead of asking every project to bolt on its own answer.