Question about Scaling of Ethereum chain

i recently brought some Ethereum and learning about it. question came to my mind that It takes a lot of memory to run a ethereum node. you have to clone the full history of blockchain that is what i read online. how long will this sustain? isnt this a very worrisome problem? this can potentially reduce number of miners day by day and centralise the mining to selected few who can run that sort of machine. like imagine a day when just to run a single node u need to download TBs of data first.