17.6% is most definitely not the right number for lost bitcoin

Here are some numbers:

17.08% of the supply is older than 10y

7.29% of the supply is older than 15y

UTXOs from the epoch 0 (up to late 2012) are getting spent all the time are their percentage keeps decreasing

Chart (with a terrible title):

10% is would be way more realistic and even then the vast majority of people of hodlers, so who knows