I just installed NVDA 2021.1 and I'll bet my bottom dollar that the voice now used by the installer is Microsoft David, which is a Microsoft OneCore Voice.
I use David as my voice with NVDA, but at a slightly faster rate, and if it's not Microsoft David it's so close that using MS David would probably suit anyone who likes that installer voice.
Brian - Windows 10, 64-Bit, Version 21H1, Build 19043
I do not understand why some seek to separate a person from their actions. The self is composed of an individual’s thoughts, actions, and expression, which are contained in and actuated by the body. What you do and say is the clearest indicator of who you are.
~ Brian Vogel