There is no danger enabling Direct Play. It is actually built into Win10, but is disabled by default.
What is a mystery is why MS have elected to not have Direct Play enabled by default, as if it does conflict with anything,
that would be a far more rare occurrence than leaving people who play old games in the dark.
I have had Direct Play enabled since doing the Win10 upgrade mid 2015 will no ill effects what so ever.
MS have apparently attempted to address this with oversight the pop up window that was introduced with the 1709 version update
that offers to 'install' Direct Play when people try to run an old game that requires it, and have not already enabled it manually.
However, it appears that this new option may be what is actually preventing some people from being able to enable Direct Play via
Programs and Features > Turn Windows Features On or Off as well, which was very rarely, if ever, a problem before the 1709 update .
Not being able to enable Direct Play is what this thread is about. Many people seem to have missed that point, including Duke,
who apparently did not read the OP's question, or other peoples answers.
Having Skype enabled seems to be at least one program that will conflict with enabling Direct Play, but apparently once enabled
Direct Play does not conflict with Skype.