What you're looking for is:

defaults write /Library/Preferences/com.apple.desktopservices DSDontWriteNetworkStores -string true

Thanks, @bpavlov . Kind of annoying that -bool worked in 10.10 and it you're writing a value of true, why is it a string and not boolean?

I'm surprised that work for you in 10.10. it's always been a string from what apple documented. I wish I could find the KB but I believe it was documented as:
defaults write /Library/Preferences/com.apple.desktopservices DSDontWriteNetworkStores true

Which if you are specifying the key type, it defaults to 'string'. Why a string for this particular preference? Not sure, gotta talk to the dev at Apple who implemented that preference.

I've heard from AppleCare that this no longer works — but the agent may not have known about or tried the string vs. the Boolean.

Existing (or new?) KB updated for High Sierra.

Adjust SMB browsing behavior in macOS High Sierra 10.13

So given the article posted by @donmontalvo it seems like the new way of doing it is in fact with a bool. Should this be effective for all users of the device though? Can I add that defaults write into our "setup script" and it will be globally applied to any user that logs in?

Our security is not particularly happy about all the .DS_Store files being dropped by all of our Mac users on our network shares.