Most merges aren't too complicated, but this one is. This is a case where there is so little info on each profile that I'd probably leave them alone, too.
While it's often a good option, I wouldn't set the profiles as an unmerged match in this case, because there isn't enough info to say they are probably the same person. David Strauss is a common enough name that these two profiles are unlikely to be duplicates. If they were named something like Romeo McGillicuddy, that would be different.
In the family of Strauss-219, there are parents and a sister named, plus a private brother, but no dates. Presumably, the manager does have dates.
For Strauss-260, the guest profile represents a person who came on WikiTree as a vistor in December 2013. We don't know if he's been back or not. He may have been using the site extensively for research, but just not adding to the tree. By looking at the names of family members, he should be able to tell if he is a match with Strauss-219.
One option would be to write Strauss-260 a private message asking him to check out Strauss-219 and see if they are duplicates.
If you hear back, then you could set them as a rejected match, propose a merge, etc., if he can't do it.
P.S. I realize now that you were talking about merging other rofiles into these lower numbers. If you start with asking 260 to look at 219, then you can ask whether he matches any of your people.