I found some potential answers online, but I wasn't satisfied with them; they often sounded slightly apocryphal ("my brother knows a guy who works in games" sort of thing). I'm hoping there are some folks here from the gaming industry who have firsthand experience implementing these initial screens.
The possible reasons I found included:
- The screen functions as a "book cover" for your game, showing the player what the game is about - It allows for preloading without the user noticing - If multiple input devices are connected, this allows the game to infer which one the player wants to use - Some platforms may require user interaction within X seconds, and the initial screen enables this somehow (?? I am curious to know more about the mechanics of this in particular, if true)
This.
Older games' "press start" messages were tied to the title screens being part of an "attract mode". This is something done both in the arcade and in retail store displays: it's much less eye catching to have the game sitting there wherever the last patron left it, than to have a rolling demo with a little trailer, some gameplay shown, and a "press start" message. The attract mode does the work of a sales pitch, and a lot of older games were big on the concept and invested time into that feature.
Attract mode serves two practical purposes: drawing customer interest in stores and preventing screen burn in by varying the content on the display periodically. Basically, it's a built-in trailer plus screensaver -- someone just turns on the game in a store and the demo runs itself until you press a button to start playing.
Companies avoided doing even a loading screen chatbox becausenof that, though I suspect the real reason is something else.
A game like Project Zomboid has fairly significant loading times even on decent machines and you can get killed in no times if you're not paying attention. If there was no "press any key to start" after the loading screen I wouldn't be able to get a cup of coffee and instead have to sit there anxiously for 20 seconds.
Of course, meeting that with a "press any button" screen is easier than for loading the full game, so they do that!