This is not a question that you simply give a yes or no answer to because like any product, even a hardtail comes with a set of pros and cons that you simply have to consider. When we look to reason why you should invest in a hardtail, you will find that on average, it is a better bike to learn hardcore biking on as compared to other more professional alternatives.
So, why is it such a good teacher? Well, for starters, riding a hardtail needs more passion, more drive as it is harsher because it does not have the same kind of suspension and rear shock-absorbing power that other bikes will grant you however it empowers the rider to ride at a speed progressively suitable to their aptitude level.
Without back suspension to streamline the hurdles that you will meet, it instructs riders to ride smoother and utilize their legs as suspension which will teach you to rely on your body as well as the bike. This will come especially in handy when you start on tougher terrain and harder bikes. When you pick a hardtail, you are constantly aware of the fact that falling will hurt way more as you will feel all the bumps. This is an excellent teaching mechanism.
Another excellent reason to invest in a hardtail is that it is mostly easier to maintain as it has less upkeep 100 percent of the time. Less pivoting capability implies less moving parts, less heading, and eventually fewer things to keep up in the longer run. Pivot bearings do not come cheap especially as they cost hundreds of dollars to maintain and thus when those need to be changed frequently; it can put a dent into your savings.