The thread title begs the question, so my answer looks defiant and counter-intuitive when I say "Yes".
Our shared tree has a real problem with dozens or hundreds of profiles that look identical in find-matches searches, because they have common names (such as John Smith or Mary Thompson) and no information about dates and locations.
It is a burden on volunteer time and effort to have to click through to each of those profiles to determine if they are sourced, what century they're from, what hemisphere the ancestor lived on -- just to create a profile or properly merge an ancestor down to the lowest-numbered profile that was created for them.
When I see a profile with no geography information coded in birth or death fields AND when I can determine where the ancestor probably was at their birth or death, I do enter a location, mark it uncertain, and explain the basis for the estimate in the change log. For example, for a profile whose parent spent their entire lives in Massachusetts, I would probably code their birth location "Massachusetts" [uncertain], or perhaps "USA" [uncertain] if the ancestor was clearly born after 1776.
I share some of your anxieties about birth date estimates and don't often make them. WikiTree's and FamilySearch's margins-for-error just aren't big enough to return all the relevant results when the estimate isn't close to whatever other bad data is out there. I do add [uncertain] and {{Estimated Date}} tags to neglected profiles with dates that are unsourced if I'm editing them for other reasons.
I'm also deeply skeptical of FindAGrave's location data, particularly because the website prohibits links to birth and death records. Copying the cemetery location in to the death location field is a recipe for propagating bad data. At most, and only for profiles where the FindAGrave user appears to have physically observed the burial site, I sometimes code the death location as the USA state where the burial is located, assuming that is consistent with any other evidence that the ancestor died in the region.
I understand that there are risks that an ancestor was born to parents who moved around a lot, or that an ancestor's remains were shipped out of state for burial, and that in those cases my bad data will propagate from their profile on WikiTree to other repositories. But unnecessary duplicate profiles and unsourced profiles are also unhelpful data. Estimating locations helps those profiles find their way to Sourcerers and Data Doctors familiar with the region who can dig a little deeper and put the profile in its proper place on our shared tree, or can determine that it is an unreliable legend or a conflated profile.
"Making stuff up" i.e., educated guesses, supported by reasonable inferences from available data, is an appropriate way to put research problems in front of the volunteers best equipped to tackle them.