ELT will not discover many new objects, it's built to do deeper followup observations of known targets. On the other hand, Vera Rubin was designed to be a survey telescope, repeatedly imaging the entire night sky to discover new objects. It will not do targeted observations, or at least very few.

Given it's passing retrograde (is that even the right way to say that?), would that make it easier to catch up and intercept?

Assuming you don't want to do anything but fly by or smash into it

Not really, the sun will be in a rather inconvenient position.

Objects can get flung out of solar systems when they pass close to large objects. Similar to how spacecraft get gravity assists.

A very rough calculation would suggested that the cylinder that goes from our solar system to Proxima Centauri contains 5000 similarly sized objects moving at the same speed:

1 object crossing the solar system plane every 5 years at 60km/s

+

Proxima Centauri is approximately 5 light years away

=>

there are `speed of light / 60km/s` objects in the cylinder.

> But seriously, why would interstellar objects come towards our solar system?

Why wouldn't they?

The "popular" understanding might even be "it's aliens!". Let me pull my elitist card, but I think it's irresponsible for journalists to use the word "visit", because it implies a thinking creature performing an action. God knows this planet has too many morons who'll see this headline and understand it to be "definitely aliens!"...

When you're dealing with objects as small as this, their weight and size is essentially mathematically irrelevant. It doesn't have any type of propulsion, so we know that unless it collides with something along its trajectory, it will keep following the same course. We know the mass and diameter of the celestial bodies that the object will be traveling near, so we can calculate how those bodies will affect its trajectory. As one of the top comments said: it has a very high eccentricity, which means it's traveling along a path that forms a very elongated, open hyperbole, so it won't come close enough to the sun to be affected by its gravitational pull if it continues to follow its current trajectory.