And I don't think the performance issue exists. Computers are fast nowadays. Parsing recfiles is straightforward. Also you could easily archive historic/old/probably irrelevant records.
Not sure if they have indexing on the roadmap, but it does make sense to me for people that have adopted it and are starting to get bigger databases.
Of course, you could argue that when the files get too big, it's time to switch to a different solution.
It seems that's kind of a natural tension in projects. Do you grow the scope to accommodate existing users with growing use cases? Or, do you draw the line in the sand and have people move on to a different solution?