WLB and Culture in Corporate Development

I always hear about how the culture at most of the Big Tech companies is pretty chill and WLB is great but just wanted to understand if that carries over to the corporate development groups at these firms too. Companies like Microsoft and Google are extremely active in the M&A market so I find it hard to believe that their corp dev groups have great WLB like the rest of the firm. Does anyone have any experience (even anecdotally) with regards to culture/WLB/hours at Big Tech corporate development groups?