As with all subjective things in audio, it depends on what you mean. What is a ‘bad recording’? Is it distorted, thin, muddy, too noisy? Or is the problem not the recording at all, but the arrangement or the mix or even the mastering?
If you've a record where the recording itself is distorted or thin/bright or too noisy, then a muffled and syrupy speaker
might make the distortion a little less audible - but to the detriment of all recordings (unless you like that sort of sound as many seem to).
On the other hand, if the problem is with the arrangement or the mix - too dense or thin or muddy, where elements of the mix are being masked for whatever reason - then speakers with flatter FR or reduced distortion can actually help. When I audition speakers, I always include tracks where the arrangement is problematic, where the mix is problematic, and to the degree I can tell, where the master is problematic. These are extremely illuminating tests for speakers. More than one speaker has performed very well with material that's arranged well, recorded well, mixed well, but failed miserably with these tests. Better speakers are able to reveal each element in the mix to the maximum possible give the recording, which allows you to at least somewhat discern the details and intent of the artists and engineers involved. The problems remain, but a good speaker can at least present all the information to you as clearly as possible.
Of course, some speakers are very tilted up (or peaky as
@maverickronin noted) - the opposite of the muffled syrupy speaker above. With these speakers, yes you may notice problems in the sonics of a 'bad recording' immediately, and conclude that the speaker sounds great but is simply 'unforgiving'. However, with more listening, it will likely become apparent that in fact all music ends up sound pretty bad due to issues with frequency response, it just takes a while for the showroom 'sparkle' to become 'grating'. As with the muffled and syrupy speaker, the tilt will be to the detriment of all recordings. Unless you like a super bright sound, which some claim to, though I cannot understand it personally.