which doesn't happen instantly. For example, the end of life of the old java versions (1.5, 7 and 8 etc) - plenty of companies simply just paid a support fee and get support, while others paid to upgrade (or even change stack).
Most open source software, even with lack of updates, does not immediately start failing. The huge amount of time and leeway, even with security issues, is what prevents it from being critical, and prevents OSS from causing a bankruptcy.