I think all of these specific questions should be open and on-topic.
Specifically, it's not part of the prohibited software listed as Pre-release, non-publicly available beta software and software granted only under an NDA
Microsoft's Office for Mac 2016 Preview is publicly available.
It also is granted without an NDA.
Furthermore, the general category should be on-topic IMO. For example, I asked a question today about something Apple labels as beta.
I'm legitimately stumped and at a standstill using this feature. I've opened two support tickets with Apple and it's been 5 days with no progress. I think there are good questions about beta software that can and should be asked. I'm of an opinion that we should close bad questions that are not precise.
We should encourage questions about narrow topics or narrow windows in time as long as they are clear and precise. If there is confusion about beta status or versions, it's up to the asker to revise and phrase the question to meet community standards.
This site aims to be the ultimate resource for community knowledge of products, and the benefits of beta exclusions seem to diminish the longer I see the site working day in and day out.
Keep in mind, Apple launched iWork for iCloud as beta in June 2013. In August 2013, it was available to anyone. Recently, they rolled it out to anyone with a Mac or PC and Safari 6.0.3 or later, Internet Explorer 9.0.8 or later, or Google Chrome 27.0.1 or later.
So, here we are 580 days after the general availability of the product and it's "still in beta" and turning down questions on a product that's in production that long seems odd to me just because it's "beta"
I'll step off this little soapbox now, but wanted to add more data than just "beta bad" or "beta good".