The difficulty could be quite high if it keeps going up. The good news is there is only so many miners they can make, and so many data centers without building more. I don't think anyone can give you a good speculation on what will happen on it.
But how can no one know what the difficulty will be? Did Satoshi make it go random or something?
It all depends on your personal factors. For example what is your electricity? And do you have a vat/income tax?
Not one size fit's all. But no for a lot right now it's not to late to start mining. But if you have high electricity price... it's not that your to late but that your factor do not allow mining.