I am adding up the costs and I thought I read here that the train prices on the SBB.ch site are not the full fare prices, but half of the price. Is that true? Is that because then easier to compare to Swiss Half Fare Pass?
That is true; it assumes that you have a half fare pass. I do not know a clear reason they do that though
I've always assumed they do that because virtually every Swiss citizen has a half-fare card. They can buy an annual card that doesn't cost much more than a tourist would pay to cover his short stay in the country.
Price box will say "1 x Individual Tickets, Half Fare travelcard CHF XX.X0". Primarily because most Swiss people get an annual Half Fare Card, and Swiss people are the majority who use the website. And partly because they want to show the lowest price, even if you have to read the fine print to realize you need a Half Fare Card to get that price.
If you go so far as to enter a name (fake is fine) and select "No Discount," then you'll see the full fare. Prices shown at https://www.ricksteves.com/travel-tips/transportation/trains/switzerland-rail-passes (or in Ricks book) are also full fare, assuming $1 = 1 CHF, so you don't have to look up every route separately.