Replace MySQL with Django. Do you assume Django itself legacy, or the Django based application? I parse it correctly as "a legacy application that uses MySQL".
That's a good question, but it's hard for me to objectively say how I'd immediately parse that, due to the close examination I've given that sentence.
You definitely have a point, though. How the phrase "legacy X applications" is interpreted likely depends on whether the context is an announcement by a competitor to X.
You definitely have a point, though. How the phrase "legacy X applications" is interpreted likely depends on whether the context is an announcement by a competitor to X.