No, but it does add quite a bit of complexity, and if it's done correctly usually requires not just a database of timezones, but also when and how they've changed over the years.
Not supporting timezones is a valid design choice, but is so important and integral it should be the first item both mentioned by a library and used as criteria to decide whether it's a valid choice for those surveying libraries.
It's sort of like choosing a storage solution. Do you need persistent storage that can survive a reboot, or is something ephemeral that works only while powered good enough? Both have their places, but choosing the wrong one for your specific use case is usually very problematic.
Not supporting timezones is a valid design choice, but is so important and integral it should be the first item both mentioned by a library and used as criteria to decide whether it's a valid choice for those surveying libraries.
It's sort of like choosing a storage solution. Do you need persistent storage that can survive a reboot, or is something ephemeral that works only while powered good enough? Both have their places, but choosing the wrong one for your specific use case is usually very problematic.