Most competitive video games hold a professional scene for a few years and then fade. The reason is structural: unlike a sport, an esport is owned by a company that can stop supporting it.
The rules belong to a company
Football's rules sit with an independent body and change slowly by committee. A game's rules sit in code controlled by its publisher and can change overnight.
That control is what makes an esport possible at all, since someone has to maintain servers, anti-cheat systems and matchmaking for a competitive scene to exist.
It also means the scene's survival depends on a commercial decision that has nothing to do with how good the competition is.
Sequels compete with their own predecessor
Traditional publishing economics reward releasing a new title every few years, because a new product sells at full price while an old one earns only incremental revenue.
But a sequel splits the player base, invalidates accumulated skill, and forces the professional scene to restart with different mechanics.
Games that have sustained long competitive lives are generally those whose publishers abandoned the sequel model entirely and monetised the original continuously instead.
Player bases decay in a predictable pattern
Competitive depth depends on a large casual population underneath the professional layer, because that population supplies future talent and viewers.
Casual players leave when the skill floor rises, and it rises naturally as the remaining population becomes more experienced. A game left alone becomes progressively less welcoming.
Publishers counter this with new content, seasonal resets and matchmaking changes, all of which cost money and require a team that could otherwise build something new.
Prize money follows attention, not merit
Tournament funding comes from publisher marketing budgets and from in-game sales tied to events, both of which track the current player count.
When the player count falls, the prize pool falls with it, and professionals move to a healthier title because their careers are short.
The exodus is visible before the game is officially wound down, which is why a scene often looks hollow while the game itself is still running.
What longevity actually requires
The titles that persist share a few features: no sequel, a competitive format the publisher funds directly, and mechanics deep enough that mastery keeps rewarding practice.
They also tend to change slowly at the top level, so a professional's accumulated knowledge retains value from one season to the next.
That combination is expensive to maintain and rarely the most profitable use of a studio, which is why it remains uncommon.