It seems that can buy a perpetual license for GBP £5000 / developer, which is equal to 16 years of monthly subscription (quite optimistic for a 3yo project).
it seems pretty reasonable to charge $30-50 a month for somebody doing the hero's work of reimplementing and building on top of a 30 year old programming environment. also there's a free one! spray money the people who do crazy niche work! that's what makes the world beautiful!
twinBASIC programming is backwards compatible with VB6 (it intends to be 100% and is very close to that now). Existing VB6 source code and forms can be imported and run (at least as 32 bit apps.). twinBASIC can compile to 64 bit and has many modern features. There is also an optimising compiler.
There is a free Community Edition.
VBA can also be replaced with twinBASIC programming.
Future plans include Linux, MacOS and Android versions.