There are hardly any till none-but there may be still some remaining anti-COvid restrictions-NOrway tends to stick to them longest. In most cases a REServ is needed there for longer distance trains-and there are reported some works along major INtern routes with bus-replacement.

Generally trains are very fine there, reliable and can bring you to all major towns. In SE=Sweden are also ´private´ hi-speed trains on some lines that do not accept passes (MTR-trains)

There are no remain Covid restrictions in Norway (or in Sweden or Denmark). I just checked the website of the Norwegian Government. 

If you have questions regarding specific trains, please give departure date, time and route and you will get advice here.

Thanks AnnaB. Goteborg to Oslo on the 27th August at 10:15 has the ‘conditions apply’ warning.  It goes on to say that the warning relates to ‘one country passes’ which I assumed did not apply to the scandinavian pass, but the same ‘conditions apply’ warning is on my ticket even after applying it to my pass.  Before paying to reserve any seats, I want to check if this is warning on everyones ticket for this route regardless of pass or if it is on mine because I am missing something about the T&Cs of my pass?  Thank you

This warning always shows up regardless of the pass you have. Not sure what it is for for this train but you're fine. Reservations are optional.

Thank you @rvdborgt