Over at telles.eu Pedro Telles (always worth a read) is laying out some more. He goes as far as to use the C-word; Corruption.
This is not something we think about in the UK, but the whole of the EU (and current) UK procurement rules are based around trying to reduce the potential for corruption. It is the elephant in the room. The mechanisms chosen are competition and transparency - competition so that unless whole industries are colluding (and it does happen) we will get reasonable offers, and transparency so that everyone (suppliers and public alike) can see what is happening and complain if we see inappropriate behaviour.
Of course you can argue about how effective it is in practice, and whether there are other ways to avoid corruption, but that is the intention.
The Covid-19 pandemic has given an excuse (sometimes justified) to circumvent the usual processes. Sometimes this has happened even when existing frameworks could have been used. It has become common to have very large direct awards without competition, and limited or no transparency at the time (or limited transparency at a later time when it is too late to do anything about it).
Now, there is a case that government is selecting good quality suppliers without having to go through red tape. And that is usually the argument made - it is efficient. Which may be true, but it is also the way you would choose to do things if you were wanting to corruptly appoint suppliers in return for backhanders or favours. I'm not saying that is going on, I have no idea. But the rules are there to try and reduce the potential for that sort of crime.
Criminals always seek to exploit difficult situations. We should be very careful, and recognise that the procurement regulations are not "bureaucracy" or "red tape" but a mechanism (however imperfect) for protecting the taxpayer. That organisations such as The Taxpayer's Alliance are quiet about this, but not about wages for public servants, shows that they are not genuine about their purported purpose but are simply pushing a political agenda. (Which in itself would be fine if they were honest about it)