Being bankrupt is not easy. For example, if you own a car it will very likely be taken from you. If you own a house you are at serious risk of losing it. Your expenditure is closely investigated & you are quite likely to have to make payments for 3 years. If you get a windfall (inheritance; lottery etc.) it is taken. If you become entitled to a pension the lump sum can be taken. You will normally find it extremely difficult, if not impossible, to get credit again for at least 6 years.
Obviously, in a lot of cases none of these things apply (other than the one about not getting credit) but when they do the money raised in these ways goes to the creditors once the Insolvency Service costs have been paid.
You suggest changing the law so that - having had the debts written off - the debtor is then made liable for them again. What is the point of that? They became bankrupt because they didn't have the financial resources to pay their debts, so why would they be in any better a position a bit later on? The purpose of bankruptcy is to allow people to wipe the slate clean and make a fresh start.
If you think its easy, I suggest you consider in detail how it would affect your own life.