Thanks for your input.
The best if you are interested with this idea is probably to submit it as a proposal on Bisq’s github
It will then be discussed. And may be implemented if there is a majority of contributors in favor of it.
This is why you can set a custom security deposit to as high as you want, to mitigate the risk.
Trader is obligated to followup on the trade when he takes the offer and if he doesn’t the other trader can get his security deposit as a collateral.
This feature could still be useful, but higher security deposits should solve this problem just as well.