There’s also a lot of bureaucracy involved in participating in the gilt market directly, rather than using an intermediary.
https://www.dmo.gov.uk/investor-information/retail-investors...
I don’t think the Treasury really wants to deal with amateurs.
That's probably true
No, but you can hold them through the standard range of intermediaries and still get the tax advantage.
NS&I offer a range of retail products - https://www.nsandi.com/guaranteed-returns is a good option but does NOT come with the tax exemption.