To judge if bitcoin is worth to invest in, you may consider this universal monetary rule:
There is NO good, easy, risk free money, that is available for everyone.
If the money good and risk free, it is called a heritage and it is not available for everyone.
If the money is good and available for everyone, its is called an entrepreneurship and its not risk free nor usually easy.
If the money is risk free and available for anyone, it is called a salary, but that is usually not very good.
If anyone claims, that money is good, easy, risk free and anyone can get their share of it, it is essentially a scam. Doesnt matter if You are being scammed with money, electricity or just waste of time. It also doesnt matter if there are several people who get scammed big time at once or millions, that are scammed bit by bit, it is still a scam. Any deal, where people are attracted with false promises and where the nature of their investment is kept hidden by purpose, is a scam. Bitcoin is not what promised and that fact is being disguised now.
Summarizing what you have stated above:
1. Taking care of your parents\grandparents would mostly give you good and risk free money only if you have good relations with them. Moreover, in this case you would be like 50-60 years old- so is it really worth waiting for so long?
2. Starting your own business is a good idea but have you ever thought about related expenses? In the EU one has to pay up to 50% of their profit for taxes..
3. Salary is OK, but it can be unchangeable for years even despite all your efforts put for the prosperity of the company.
These are actually the reasons why people still follow false promises. Personally I am very much disappointed with the increasing number of scams that really disguise the whole idea of bitcoin and blockchain.