No it's not, the money you have monthly might be the same for a lot. But there's a big differences psychologically and socially, that you don't have to work just to survive. I can quit my job without having to fear how I'll survive. I can decide to get further education without having to think about how I'll do that financially (at least in Europe). Etc.

It's very big difference compared to just lowering taxes (granted we're not talking about negative income tax which may indeed result in the same thing as UBI).