Brake discs at the Renault Kadjar

Hello, have a Renault Kadjar BJ 15 drove 37000km without any problems up to now. So I am 65 years rather the cozy driver. When changing tyres in Nov. I noticed that the disc brakes are quite finished and also in the workshop they told me in the summer 2020 at the next inspection you have to change the ones.. I was quite surprised that the discs have driven down so. Are the discs too soft or the blocks too hard or whatever!!! New discs are available from many manufacturers from very cheap to very expensive.. Now my question…what would be recommended to me… and no it is not my driving method!!! Mfg