Developers were told 32-bit apps would be phased out in spring 2018, not earlier. Some apps require extensive work to become 64-bit clean and modernized. A couple examples are EyeTV and Inkscape. Both these apps have release versions that are still 32-bit, but the developers are working on 64-bit clean beta versions.They did it incrementally over ten years. I find it difficult to call that premature. We all knew it was coming.
If the announcement had been made earlier, say 2015 or 2016, I might agree with you. Three years is enough time, even for smaller developers without a lot of resources to work with. And any consumer who considered purchasing a 32-bit app during that time would be alerted by MacOS that it would stop working in the future.
Edit: An incremental phaseout would look like this:
- Apple makes the announcement in 2015.
- Alerts start appearing in MacOS in 2016.
- The alerts become more aggressive in 2017.
- In 2018, MacOS loses the ability to run 32-bit apps without changing a setting or using a simple Terminal command posted to Apple's website.
- In 2019, finally, support disappears entirely.
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