That's basically the definition of "gaming the system", tbh. When someone is "gaming the system" they aren't breaking the rules, they are simply taking advantage of the process to reach a conclusion that wasn't the intended result. I think it's safe to assume that Steam's refund policy was not intending to allow players to play paid games for 20 or 30 hours (potentially to completion) and receive a refund.
When I say the policy is "stupid" or "brainless", I'm not talking about the posters here or even the players getting the refunds, but the business practice that is allowing it. In this case that is Steam.
If players want to advocate stealing the developers work that is their prerogative to do it. Honestly, it is slick on their part if they know that Steam provides them the ability to play as much as they want of a game offered in early access and still get the refund. It certainly undermines the relationship between the publisher/developer and Steam though. IMO, I think the 2hrs is reasonable enough for a refund period or maybe 3 or 4 if you wanted to really push it. 25 or 30hrs with a refund is too much because at that point you are reaching what might be the average amount of time a player might spend with a game regardless of if they finish it or not.
It is irrelevant to this particular game, as obviously people are liking the game and RPGs have hundreds of hours in them, thus this issue is nothing for Starfield. But, I still think it is poor policy on the part of Steam, especially for more linear games that might want to offer an early access perk with the premium/deluxe versions of their games. Potentially they would have to skip Steam and release on the Epic store or something (at least for the early access period).