I guess it does make their communication feel a bit more personal, especially since they usually don't use corporate language on personal twitter accounts.

It’s just a different form of sanitized corporate PR even if the voice is tweaked for the medium.

At least traditional bland corporate PR doesn’t try to build up a weird parasocial relationship with the product owner/dev trying to act like your buddy, and per OP also often follows a consistent process without memorizing the personal handles of the current org chart.