so I was just watching on TV all the inventions of the last 100 years, and was thinking that these days it is harder to invent new products, than it was say 20 to 50 years ago? since I guess most things are invented already. OR with the new technology and internet, is it harder to invent a new product?

you can use the new electrical components to invent a new product, if you can think of something that is needed. I'd say there is still much scope for inventions using new components, technologies and materials.

How about things that haven't yet benefited much from the information age, like toilets for example.

There are actually more opportunities for invention. Usually invention takes place in adjacent areas of use, similar to how Evolution works by pushing at the edges of niches. Eureka moments will always be rare and Paradigm-shifting insights even rarer still.

Yup - back in the late 1800s, when that guy Marconi was pondering the radio and the future world of electronics, his soul-destroying thought was that everything had been invented already.

Exactly this question was being asked 100,,,and fifty ,years ago.

Inventing continues though.

With more inventions comes more ideas to work with. Most of the inventions today will probably be obsolete 100 years from now so there will always be room for more inventions.