Didn't used to be, except in extreme circumstances. Was seen as a really bad sign.
To the extent there's "science" on this, it's a lot less clear than you might think that a policy of reaching eagerly for the layoff-button is long-term beneficial to companies, i.e. there's a good chance it's a cultural fad, you do it because "that's what's expected" and perhaps investors get skittish if you don't, for the circular reason that... that's what's expected.