(Disclaimer: I am not a copyright lawyer.)
No. BOSL is basically equivalent to GPL, except for one specific difference (that makes it mutually incompatible with GPL unless specific exceptions are present): Derivative Works (i.e. code that incorporates, extends, or changes any BOSL-licensed code) may be licensed as non-BOSL for up to 12 months from first being used publicly, after which they become BOSL-licensed.
Put another way:
- GPL is a strong copy-left license. If any GPL code ends up as part of your binaries, your source code is required to be immediately open-sourced, and immediately also be licensed as GPL.
- MIT is a permissive license. It places almost no restrictions on how code may be used, and you can use it in codebases with any license (open source + copy-left, open source + permissive, closed source, whatever).
- BOSL is a “delayed” copy-left license. If any BOSL code ends up as part of your binaries, your source code is required to be immediately open-sourced, but it is not required to be licensed as BOSL until 12 months later (but you can choose to license it as BOSL sooner, or immediately in which case you’re basically doing GPL).
So if you’re comfortable with using GPL-licensed code in your projects, then BOSL can be used basically equivalently (by just ignoring the 12-month timer and immediately licensing your Derivative Work as BOSL). But BOSL can’t be used equivalently to MIT (or automatically convert to MIT after some time), because BOSL has the same kind of virality as GPL (more slowly, but still there), whereas MIT does not.