Some other bridges have barriers around, but not connecting to the pylons.

Those are great for little boats like one of those superyachts. They become dominoes that hit before a boat like this: https://www.vesselfinder.com/?imo=9697428

Absolutely. 116851 long tons deadweight, which the Google info box says includes everything (busy now, so can't check in detail). That's 120,000,000 kg, so a little bit less than I guessed. Now looking at 10km/h or 6.2mi/h or 2.78m/s, that's enough to come up with a big E for E = 1/2 * m * v². The momentum p = m * v is also rather unpleasant. If the momentum was suddenly transferred into my 2,000 kg car (e.g. if the ship hit my car), I could do my work trip in about 1s, though that's only a few times times faster than the ISS (which travels at 7660 m/s).

[I'm very busy, so hopefully I didn't forget/add a few 0s by accident. Anyone feel free to correct me if I did.]

You were on point. Separately, I also used that rounded figure of 200k tons. The Deadweight plus the ship and fuel should easily get at least very close to that.

Right. I am not really thinking of designing pillars that are impossible to knock over. I am thinking of alternative bridge designs where a higher percentage of the total bridge stays up when one pillar is taken out.

On this bridge, the main section of the bridge is supported by four spaced pillars, making three main spans there. One of the middle two towers was hit, so this should affect two of the three spans. But it took down all three of them. A span that was supported on both sides by intact towers still came down. That is what I find most surprising here.