No, everyone must not invest in bitcoin but should it comes to that in the future it's going to be one of the best investments choice everyone will be making. People that invest in bitcoin don't invest in because it's the only option of digital asset they've available to them, of course, there are dozens of investment options, but when wanting to invest into any asset there are particularities that would have to attract you which other supposed assets are lacking. When we look at limited supply, decentralised, a store of value and hedge over inflation and many more, these are features that bitcoin is known for, which many others so-called fiat related assets lacks.
What you said here are very true, it's not a must that an individual must invest in bitcoin, but due to the options available, and it's one of the best asset to invest your hard earned money in now, and even in future time to come, it's wrong to pass on the opportunity.
where the problem are is that most investors tends to substitute Bitcoin with alt and shit coin which is a terrible idea to me, but if you are substituting it for land, real estate and gold, it's more logical and better than engaging in alt or shit coin that are not reliable for an extended period of time, so what am trying to say is that it's true that it's not a must that you must invest in bitcoin, but it is wise to consider it when looking for what to invest that can generate a better ROI in the future.