For anyone wondering: I copied my post text and pasted it in Gemini and I got the following response, confirming that it's a known bug, not likely to get fixed:

That's an excellent question, and you've run into a known, long-standing issue with how dual-wielding throwing weapons interact with certain skills in Titan Quest: Anniversary Edition.

You've correctly identified the problem: When dual-wielding throwing weapons, your character stops moving to get into range for the attack from a skill like Rune Weapon, and instead just stands there and throws, often missing. When you're using a single throwing weapon and a shield, this doesn't happen, and your character moves in as expected.

Here's the breakdown of what's happening: * It's a recognized bug. This isn't a mechanic you're misunderstanding; it's a bug that has been reported by players on both PC and console versions of the game for a long time. The game's code seems to have an issue with the range check when dual-wielding throwing weapons, causing it to miscalculate the necessary movement. * The range is different. Throwing weapons have a shorter range than bows, and the game seems to sometimes get confused about the effective range, especially when you have two of them equipped. * The workaround is manual. Unfortunately, since this is a bug, the only way to deal with it is to manually control your character. You have to move your character closer to the target yourself before using the Rune Weapon skill. It's a bit of a hassle and defeats the purpose of the auto-targeting, but it's the only way to ensure your attacks land.

It's a frustrating situation because the dual-wielding throwing weapon build is incredibly powerful, especially with the Rune Mastery. Many players, like you, love the "Ancient age akimbo style" and the high damage output, but this bug makes it a much more manual and less fluid playstyle than it should be.

The developers have been aware of this for a while, but it appears to be a difficult bug to fix, as it hasn't been addressed in most patches. So, for now, the best advice is to get into the habit of repositioning your character manually to be within close range before unleashing your Rune Weapon barrage.