BI, does not remove the benefit from traditional employment. Rather it removes the bureaucracy and cutoffs around traditional government benefits. Currently, you get no benefits if your disabled for 5 months and a significant check if it's 6 months. With BI, you get the same money either way, and while it's probably less than the 6 month benefit the risk reduction is worth a lot.

Better yet, get laid off and want to try making iOS apps? Just do it, your benefits are unaffected if you want to start a company.

Now, the downside is currently upper middle class people get higher disability benefits/social security payments. With BI that goes away, society does not care how old you are or what you made you get the same basic income as everyone else. So you better have savings if you want keep living in a high cost of living area.