GNSS track sufficiently accurate?

Hello,

I recently climbed ;-) a peak in a south-eastern European country
that was almost 1200 m high. The individual route positions were
determined and also recorded by a Garmin GPSMAP 64s by evaluating GPS
and GLONASS signals; for optimal reception of the satellite signals,
I used the (external) Tallysman TW4421 antenna, which is optimized
for receiving the satellite systems mentioned:
<https://www.farnell.com/datasheets/2860212.pdf>

The antenna in question was in the compartment provided for it in the
baseball cap specially developed by Trimble

<https://www.directupload.eu/file/d/8672/cb3gyk7a_jpg.htm>

which I, as a freak, had of course put on ...

Here is a report on the advantages of using this antenna:

<https://www.navigation-professionell.de/garmin-gpsmap-64-externe-antenne-tallysman/>.

But now finally to my question: After comparing the course of my
tracks in the summit area

<https://www.directupload.eu/file/d/8672/fkikpcbu_jpg.htm> (thin blue
lines, outward and return routes)

I had to realize that "my" route deviates quite significantly from
the OSM route (red dots). I am now wondering whether my track is now
sufficiently accurate to change the OSM route accordingly. After all,
the reception was always optimal thanks to the device configuration,
and the outward and return routes are more or less congruent. What do
you gnss experts think?

Many thanks in advance for your opinions!

Best regards

Reinhard