Am i right to assume that rich people dont have much personal savings, because the vast majority of their money is pumped in investments?

Depends. Some could be asset rich and cash poor. What's the definition of rich?

But in general, they do tend to allocate 80-100% of their investable resources and make money work for them.

From the videos I watched and books i read, personal savings (in the bank) is the last thing rich people put their money in.

OF course no doubt cash is king, but they would mainly invest it in assets.

All sorts of assets , properties, businesses , paper assets like stocks.

oh and FYI im not rich, im changing my mindset towards that direction so i understand what these rich people do to become richer.

Do read the book rich dad poor dad, that book opened my mind in everything.