If anyone go there with their wife, please let everyone know if it's also impossible to do multi-entry with wife present. All the report so far are people trying without their wife being there.
I can confirm that the info is very recent and valid. No issue if you apply for Non-O, but major issue if you are trying to get tourist visa with previous history of many Covid extensions, Ed or Volunteer visa.
In brief, wording matter. "Land borders" is a general term. A specific border will have specific ruling varying from: never ask, sometimes ask, always ask.
Yes, many "land borders" will ask, but that's not what we are debating. You said this "I've come across accounts of people being asked for the three proofs at every crossing I can think of", which is factually incorrect. Many borders like Nong Khai and Mukdahan will never ask for the 3 proof of. And you wont find anywhere on the internet people denied their 2 visa exempt entry per year at such borders.
No, you cannot be asked at "any time". It depend entirely on the border you are trying to enter from.
No, you have not come across people being asked for the 3 proof of at "every crossing I can think of", this is factually incorrect. Mukdahan, and especially Nong Khai, do not ask for this ever.
Your friends were not doing a border run in Laos.
Onward ticket is well known and people who enter by air often use it.