If the LFN support hype is mentioned, you can bet it’s no actual user of DOS programs. Fixated at the command prompt, DIR this, DIR that, complaining about missing LFN’s (of non-DOS files). LFN support has already been questioned for gaming, it’s as useless for non-gaming. LFN able programs are mostly utilities w/o any practical use nowadays.
Database programs should function properly in DOSBox. You only can’t use them in a multiuser setting. If more than one instance of such program is running, the database files will in time get corrupted. But if you are a single user: No problem.
DOS database programs are still useful, else they simply wouldn’t have survived (like crappy games didn’t?). Porting those programs to a modern OS is often no option, not just because of the costs (10’s or even 100’s of thousand dollars). Many porting projects stranded because those fancy new programs with lots of bells and whistles couldn’t deliver. DOS database programming (text mode) was all about functionality, in modern OS’s seemingly mostly about looks.
Using databases is a another ballgame than using a complex program manipulating data stored in databases. For just maintaining a database, there are lots of modern options.
What would the features of DOS-era printers be, besides carbon copy of dot matrix printers?