I wouldn’t want to speak for dozens on this, but I’ll refer you to 24:55 of this video which answers the your question partially (nonetheless basic idea that I’ve gathered is they’re not a bank so have to replicate a savings account until they are and they’ve come up with “Trust Bonds” as a short term proprietary solution i.e. hoping to gain your trust by literally placing your money in a Trust & using their marketing budget as a loss leading strategy to prefund the interest. Furthermore, they’re listed so that they can be ISA eligible I believe and education is a big part of why they’re bonds too. It’s part of demystifying investing for the average joe - once they’ve become comfortable with “Trust Bonds”, they may gain the confidence and capital to take on risk with real EM Bonds & ETFs in the Invest Section of dozens):
You’ll find further official answers in the other Ask AC vids (but I listened to them a while ago so won’t go back to find time stamps) but you’ll probs get a better answer in the Seedrs pitch deck or discussion forum in coming days anyway.