The most commonly cited reason for the ~29:59 limit is regulatory/tariff classification: in some markets, a camera that records longer can be treated as a camcorder rather than a stills camera, which can affect duties or licensing. That’s why many still cameras stop just under 30 minutes.

There is also a separate file-size limit on FAT32-formatted cards: a single file can only be about 4GB. At high-bitrate 1080p, some cameras hit that size limit before 30 minutes. In theory manufacturers could span files automatically, but many DSLR video modes were designed as secondary features rather than for uninterrupted event recording.

Based on the answers here, heat is not the main explanation for the standard 29:59 cap, since many cameras can start recording another clip immediately after stopping.

So yes, the limitation has been common, but the reason is usually not sensor overheating. It’s more about product classification, codec/licensing considerations, and file-system limits. If you need long continuous recording for concerts, weddings, or lectures, a dedicated video camera is often the better fit.