In my personal work experience, LightWave is typically used by small teams tucked away in studios of all sizes. It's well suited for a small group of artists supporting big projects. The Box at Rhythm was a good example; we were considered an 'alternative pipeline' because we used off-the-shelf software and had our own separate 'mini' pipeline, and we handled the work that might have been too costly for the studio's 'big' pipeline.
What I can say about my current work is very limited but maybe this much is okay. We use both LightWave 2015 and 2019, and we gradually shifted towards the latter this past year. Most recently, it was used for the opening 'T-Rex' sequence for the Jurassic Park TV show. (I wasn't involved with that assignment; I'm on a different show.) I'm not sure we have 2020 in-house yet; maybe for testing. Of course we also use other software, including Maya, Nuke, After Effects, etc., whatever gets the job done quickly and looking good.
While I don't have numbers to support how it's used at other studios, I do have friends in similar work situations. I'm sure the LightWave share is much smaller than when I started back in 1998, but it's still present.