I don't think this is going anywhere ("vive la difference"??), and I can but presume that we are thinking/talking about different 'agendas' (for an investigation/Inquiry). As I previously wrote, I can think of at least two such agendas:The "government" is not an independent sentient entity. It may be legally independent, separate, but it has no agency by which it can make its own decisions, issue its own directives, etc. .... Whatever "the government" does, it is actually people who did it, so of course we have to consider the people involved - there is no-one else.
1... "Accountability". This will very commonly relate to individual(s), although concepts such as 'corporate' or 'institutional' accountability may sometimes bee relevant.
2... Learning lessons from what the way in which the Covid-19 pandemic was managed in the UK, in the hope that such an exercise would help us to "do better" if/when we face any similar situation in the future.
My personal interest is primarily in the latter. In that context, all that matters is what was decided/done, how well that worked, and, with the benefit of hindsight, what could have been 'done better' (and hence could be 'done better' in similar situations in the future).
In that respect, all that matters is the "what", and its results/effects, regardless of any considerations of "why" or "by whom". It doesn't matter a jot as to whether the decisions that lead to the "what" were made by an individual, a small group of individuals (maybe the Cabinet, perhaps determined by secret ballot), a larger group of individuals (maybe a secret ballot of all MPS), a very large group of individuals (e.g. referenda of the entire electorate) or, these days, even 'by a computer' (or, in the case of finely-balanced decisions, even "by tossing a coin')
Some people (presumably including yourself) would like "accountability" to be investigated 'for it's own sake' - which I suppose would be fair enough (as a separate investigation).. However, I cannot see how such investigations would help us with future planning or future actions. For a start, non of the individuals, or groups of individuals, will be in government 'when it happens again'. Secondly, if one believes (as you appear to) that some of the ';wrongs' of management of the pandemic were the result of acts which were criminal and/or in violation of parliamentary rules, then, as far as I can see, the only lesson that could be learned would be that "in future, members of government should not commit acts which are criminal and/or in violation of parliamentary rules" - which I would suggest would not be a very useful (or 'new') "lesson learned" !!
Kind Regards, John