If you look at a satellite image, you quickly see that there just isn't that much space left to nature. That is true for most of central Europe. Doesn't mean it isn't green, but pristine forests don't exist anymore. There are some spaces left to itself now, but they were still touched by human cultivation.
Pristine is a very high bar. There is archaeological evidence of semi-settled early agrarian existence where they would slash and burn an area to farm it and then once the soil depleted move on to a new segment of the surrounding forest and abandon their old settlement to be overgrown and renewed. Wasteful but the cycle was fully sustainable.
Even without human involvement we would see some "normal curves" to tree diameters via attrition of the oldest for varied reasons - but their ring count would be higher.
