Very correct. Hell, OP is even thinking way too far out of scope for the goal on the request itself. They are thinking of their own progeny. The website doesn't need to survive 100 years, that implies knowledge of the site existing survived their death too. Only a method of seeing it, and reminding their children of it are needed, which honestly only requires the same attitude as keeping a an album of picture around.

OP could just get a box with a Raspberry Pi 5, its power chord, a mini mouse, and a built in mini screen. Seal it all off so nothing inside shakes. Congrats, you got your very own digital version of a personal memoir. The only thing now stopping this from working is The International Electrotechnical Commission somehow doing in the next 100 years what they couldn't the previous 120.

The screen can either, screw it, show the content directly, or MAYBE some indication of what a SSH connection is so the people accessing it have a way to figure it out. It's fine, the hyperfuture AI will do it for them.

Every 5 years, OP opens the box, and put in a new SD card with updated content, labels the previous one, and closes the box. Or, I dunno, swaps out the device for something else newer, if the IEC ninjas did come for him and forced everyone to use Wario Logo shaped plugs.