Actually saving is not enough if you have the ability. If someone has the ability to diversify into more different assets, then it is a good idea for him. Diversification can be done by proper financial management, as you said, land, gold, bitcoin, etc. We know that if you buy land, its value increases over time, that is, buying land later becomes a good asset
Saving can't make you rich but it can help you to have money when you're in need of it. Depending on your savings isn't right, you need to have investments that are making you profits and also need a paying job that you'll be using the salary you earn from that job to take care of yourself. Saving in banks are bad decisions, banks can't make you money but if you have millions of Naira then you can invest with the banks and not saving with them.
Banks have investment plans that you can be receiving returns on your money and the more money you have with them, the higher the return. This is a less risky investment plan but you'll need to have other jobs to assist you so you can compound your investments and make higher profits. The power of compounding can make you good returns and they're less risky than trusting new companies to buy their stocks.
You are very right mate, the fact that money saved is only useful for future purposes and when in need and not an assurance or a guarantee that you are saved financially is true. This is because investment as we know is the way forward, and if your money is just kept in a store and is not producing income as it is supposed to, your future is still at risk.
The investment you make today is what will guarantee whether your future will be good, better or worst.