Is it me or all those rules about fighting with two weapons. crossbows, equipping weapons, etc. are needlessly fiddly and annoying?
Yes ... and no. Let me start by saying that for 95% of players, and for 95% of use-cases*, the rules work great! Because most people aren't going to care too much, and they aren't going to be constantly sheathing and unsheathing weapons during their attack.
And I would say that while the rules should have been made more clear and not distributed to different areas like they were (why is the default rule for TWF in the light weapon property???), once you understand the basic concepts, it's pretty simple.
However, I think that the because the rules are all over the place (both figuratively and literally all over different sections), the remaining cases start to get weird. It's seem clear that the
intent of the rules is to try and regulate "too much" weapon juggling and get rid of weird "dropping your weapon" manoeuvres. But it doesn't ... quite ... do that. Some things will always be allowed (thrown property), other things are bizarrely unclear (hand crossbows, ammunition property), other things are just weirdly underdeveloped and left to interpretation (does the free object interaction
include weapons, or is that disallowed because of the specific equip equip/unequip in the Attack Action?).
Then there are other weird interactions they might not have thought of. For example, there are weapon attacks that don't come during the Attack Action- they occur during the Bonus Action ... or ... the Magic Action. But the Magic Action is cast a spell.** So if you're a spellcaster using a Magic Action to attack a critter with your weapon ... um ... what? How does that interact with the rules that are specifically in Attack Action for equipping or unequipping? Maybe just don't think too hard about it.
In summary- I would argue that the rules neither prevent abuse particularly well (if that was a concern) nor are written well for edge cases. They are "good enough" most of the time, but those edge cases really are rough. IMO, YMMV, etc.
*My statistics are guaranteed to be mostly truthy, but it you prefer, substitute "the vast majority" for "95%".
**That's why an ability, like the EK's War Magic, that moves a cantrip into the attack action are so valuable.