The linked article has a section addressing this. It says that in later periods some doctors recommended not bathing.

Some indirect evidence comes from historical perfume recipes. They really liked strong stuff back in the day.

King Lear: "Give me an ounce of civet, good apothecary, to sweeten my imagination: there's money for thee"

Now, Civet here is a by-product of anal glands of a civet cat (not really a cat) and it smells pretty much like you'd imagine: extremely fecal, pungent and long lasting.

Modern perfumes still use this ingredient sometimes in minuscule amounts, but one ounce of civet is a lot for a modern nose. it would stink up the entire king's palace for days or even weeks.

Off-time but not off-topic, an exceptionally good story is narrated in Perfume by Patrick Süskind:

https://en.wikipedia.org/wiki/Patrick_Süskind

https://en.wikipedia.org/wiki/Perfume_(novel)

What many people forget today is that we are now (with the obvious exception of smog/pollution and related) mostly living in odourless environments whilst the air in a city, at least until the 18th or 19th century was full of very strong smells.

Only think of:

1) open gutters/sewers

2) "side effects" of ubiquitous animal traction

3) small shops/industries (using fires, chemicals, etc., one example for all tanneries) were often side by side with homes

Medieval Europe is several hundred years, a load of different societies at any given time, social strata within these societies. And even then, are sources reliable? If a lot of writers in a time period write that people don't bath enough, is that a sign that everyone is concerned about hygiene, or a sign that people aren't concerned about hygiene?

Indeed, all that is made more challenging given that "ordinary life" was often not considered a subject that should be written about any detail. I recall a description of medieval literature often involving "the acts of kings" written as just as a sequence of events.

I think in many societies, there often wasn't much effort put into "telling people what they already knew" and instead writing involved records of big events or accounting entries.