BOM should be more widely used since the introduction of bundled apps. Clients didn't used to license it if their primary bills were actually kits, but when it is included, they use it.
Work Order has never been a big seller, because:
1. Many resellers don't do manufacturing.
2. It generally is not a great function, unless you add enhancements.
3. Clients initially don't want to automate this and have other systems in place for tracking production.
Actually the developers (such as ASC Group) have done a good job of introducing enhancements that make the module much more usable to the point where I believe there is more of a market. It certainly does not have the full functionality of JobOps, but it is a less expensive alternative with the enhancements.
Sage does not look at the above with regard to whether to convert the module any more than it looks at JobOps seriously. That's why Sage 100 is in ""maintenance mode"".