TSM win because they have to

While true that almost all satire is in writing takes place with some form of a literary device like writing, it is not 100% restricted to just that. The same can be said for sarcasm in that it almost always is in vocal form, and that there are no absolute restrictions or limitations. So saying that since it is in writing it has to be satire is incorrect.

Satire usually is used to indirectly ridicule or make fun of a topic in hopes to demonstrate a point, situation or contradiction in order to provoke or prevent the changing of a subject.

Sarcasm is directly pointing out something in order to deliver either a direct or opposite result, such as when you say the opposite of what you mean, but people still understand your goal. It also tends to be more cruel or mocking in its delivery than satire.

Both usually make use of humor as a means of conveying the message, while still keeping the overall integrity of the actual message.

If TSM lose then all their 10 year old fans will no longer buy RP to get those TSM logo icons.

Since this is a direct "attack" on a specific group and not used in any clear way to either provoke or prevent change, it is sarcasm.

Now, if your goal was to try and make a point about how the big name brands like TSM winning can affect the success of in-game store item purchases such as TSM logo icons. And how you think that there might be some hidden incentive for the big name brands to win to promote players, specifically younger players around the 9-11 years old range (average is still 10 years old), to purchase their team's icons, then yes that would be more satire than sarcasm.

Or, if you were posting that TSM is a team who holds a primary fan base of younger aged people and that they possess a large enough threat to the TSM company as a whole to merit a necessity to win games or have severe consequences with the sales of their merch then that could be considered satire as well.

Both of these could be considered satire because they indirectly try and connect 2 points while trying to bring attention to an issue you think exists in order to provoke change or prevent change (it is unclear to me which you desired).

However both of these seems unlikely to be your intention and they seem to be more similar to conspiracy theories than satire. The second one is impossible as well as ridiculous. To think that a large name like TSM who holds many sponsorships (like GEICO, Logitech, Kingston Technology, and HTC) would still have a need to win in order to either make money, or keep sales up. TSM isn't getting any less popular. Sure they had a bit of a rough patch, but they seem over it now and should be back in full swing. But that rough patch did not hurt them in terms of sales by any large margin. Fans will be fans regardless of how successful you are. Winning more obviously adds more fans. And losing may lose some here and there, but those amounts are nowhere near the same. You always gain more than you lose, unless some form of scandal or generally unliked event happens. For example if TSM were caught cheating somehow, then the name would suffer, but losing a game would never have that much of an impact. But as I said, these are not necessarily your intended meanings by your post, and that they are just ways you could interpret what you said as satire.