I never knew that!This is not the case. There is no restriction on Irish residents buying UK Premium Bonds. See https://www.nsandi.com/i-live-outside-uk-can-i-invest-with-nsi
From the link:
If you live outside the UK, you should check whether local regulations permit you to hold Premium Bonds. For example, the US has strict gaming and lottery laws which mean that it may not be possible or practical to hold Premium Bonds while in the US.
If you are allowed to hold them, you will have to apply in the first instance by post. Once your holding has been set up you can register for our online and phone service.
I checked with the Irish Revenue some time ago. Buying UK bonds is fine and they treat UK Premium Bond prizes for Irish tax residents exactly the same way as Irish Prize Bond prizes - tax free.
It looks as if the block on downloading an application form is temporary and due to coronavirus. I would also guess that they are not currently processing any new paper applications using the forms available at UK Post Offices. From a pop up on the NS&I entry page:
Our phone and postal service is limited and experiencing delays during the coronavirus outbreak, as we’re working with much smaller teams. We’re asking our customers to do everything they can online. This will help us keep our teams available to help those who need us the most.
You would be OK to purchase bonds if you already have a working online/phone account, but new applications from overseas (which must be written applications) seem to be on hold for the moment.
Limit is £50k per individual (vs €250k)
The overall payout is 1.4% vs 0.5% (reflecting different interest rate environment)
The distribution is better with 1.2% being paid in £25 prizes
So let us compare £100k Premium Bonds vs €100k Prize Bonds
Premium: average 48 prizes of £25 p.a.
Prize: average of 7 prizes of €50 p.a.
So Premium Bonds offer both a higher expectation and a lower relative standard deviation of returns (14% vs 38%)
The exchange rate risk for an Irish resident has already been mentioned but if you have sterling liabilities or if you would like to diversify a bit the risk of a Euro wobble then Prize Bonds look attractive.