No matter how many bitcoin you hold you can still misuse the money, so we should understand the concept of Richness and Wealth.
The amount of Bitcoin you save won't change but the value of those Bitcoin does. By holding Bitcoin especially in next few years, the value would increase like in past several years thus people always have been saying that holding Bitcoin is beneficial because you can get profit from there (hence holding and invest on Bitcoin is interchangeable).
Unlike fiat the value of that fiat is decreased because of inflation, so your post doesn't make any sense here.