$250K coverage is absolutely necessary. The 100k provision has been in place since early 1970's, and has never adjusted for inflation. Many people have over 100k saved in IRAS etc, but most importantly small to mid size companies have well over that as they escrow for large expenditures like inventory, payroll, taxes, etc.
The lack of such provisions will put many prudent business men an woman, who worked hard and acted wisely to build up cash and not buy the big house or spend lavishely, into a state of contraction.
What would a wise business owner do when he is sitting on sizeable amount of cash, his firm is returnng a less than expected profiit in the short term, and the prospects of his capital savings being secure are unsure at best.
He closes up shop, lays workers off, liquidates working capital and lives off his savings. He will most likely land a job in a consultant position and ride out the storm to better days.