Around 4.0G on the ride up in a space shuttle experienced with feet above your head.It is... but they don't get anywhere near that in a human launch. Significant for the time they feel it, but not a ton. And the biggest issue for most mechanical objects is the vibration by far... but as mentioned, the watch won't really experience that.
For the Apollo missions, max G was on reentry and topped out for each mission like this. G is significantly less of a problem for a human while experiencing it reclined - that sort of G is called Gz. Even if an astronaut was to momentarily experience G-Loc, they'll snap out of it when G loads subside.
My Breitling gets occasional exposure to 10G + for short times and the watches take it in their stride.
Maximum G at Reentry
This graph is a Saturn 5 rocket launch