I'm aware of most of these platforms (Mintos, PeerBerry, Robocash, former LendingClub etc).
Some are focused on persons, some on real estate (like Estateguru) some on companies etc.
Two things connects most of these platforms: Risk and Regulation.
People or companies that need money and couldn't get a
loan at a bank - they go to these platforms and lend at a much higher interest (and unfavorable conditions in general).
Higher interest = higher risk.
Also, many of these platforms are not regulated or they move their businesses to countries where with less (or no) regulation.
So it's all good while it lasts - but once the s**t hits the fan - the investor could lose everything.
If you just search you'll find many of dead platforms where investors lost millions.
Even the website you shared has this disclaimer even above its logo:
"Don’t invest unless you’re prepared to lose money. This is a
high risk investment. You may not be able to access your money easily and are unlikely to be protected if something goes wrong."
And then it says
"Earn 5-12% p.a.*
Income is taxable. Reinvest monthly income or withdraw
cash. *Return after fees, before bad debt. Not covered by FSCS - capital at risk"
So you might earn 5-12% per year and then you need to take from that: tax and bad debt that's not insured. LOL