now decentralized exchanges are at the experimental stage and they constantly transform their code and become better, so that in the future they could not be hacked
If they are in the experimental stage, should we wait until everything is tried and tested or we should completely jump into these DEXs as they seems to be more promising than CEX?
That is up to you and what do you want out of a trading platform, if you want convenience then keep using centralized exchanges they are very good, fast, reliable and have huge volumes that allow you to exchange huge amount of coins with no problem, the problem is that you do not know when they could scam you and take your coins or revert a winning trade or ask for your personal information in order to verify who you are.
Decentralized exchanges still have a lot of issues to solve but the most important is the volume that is so low, and in many coins you only need a couple hundred dollars to crash or pump the market but if you are willing to accept those inconveniences then you can use them without any problem.