The problem is really the perspective we have while inside our ships, plus the speeds and distances we are dealing with.
When I began to tackle Anacondas, I was flying a Vulture, and indeed, the Condas didn't seem that massive. Okay, they were big, but it didn't seem like they could double as carrier like the in-game description says.
...That is, until I was flying with a wing that included new players, and one of them was flying a Sidewinder. When he saw my Vulture getting closer, he said "WHOA, your ship is HUGE". Then I went to a screenshot with a top-down view of the Vulture. I made some pretty rough estimations, but this ship is probably close to 40m long (which is roughly about 2.5 Sidewinders). And that's because I don't have a direct way to compare it to an Eagle, which has an estimated length of 29m (roughly two Sidewinders). And the Viper is bigger than the Eagle (35-ish meters or more, maybe?), and the Vulture is even bigger (being actually the biggest "small pad" ship in the game, apparently).
And the bigger the ship you're flying, the smaller the others feel in comparison, specially when you're not measuring your speed in kilometers per hour, but in meters per second (3.6x multiplier). For example, that 400m/s boost? That was actually a 1440km/h supersonic dash, roughly the low-altitude top speed of a F/A-18F fighter jet - considering that the F/A-18F will run out of fuel after roughly 4000km, meanwhile you can travel in the Mm (Megameter, or million meters) scale without breaking a sweat.
Also, as a matter of comparison, the average urban bus is about 12m long (18m if it's articulated).
TLDR? Ships in this game are BEEEEG. So big you get used to it and don't realize how big they are.