Howdy,
I play Siege from Beta, so I feel I can provide value to people that also love the game.
From the first time Ranked came, I dabbled in it on constant above-average levels. I also participated in clans and esports teams; let me introduce you to a concept that keeps me playing well.

One thing, one strat that balances my ineptitude to hit headshots.
One thing that stays constant in an ever-changing meta of Siege.
One thing that acts as a lighthouse in the sea of possibilities that the enemy can throw at you at any round:

Outsurprising the Enemy.
Simple thing, but listen; there is a reason why Diamonds get clapped by Golds; that reason is that Golds can let loose their inner chaos goblins and ruin the otherwise predictable meta that top players adhere to.

Combining a solid game sense with a hefty sum of surprises can turn any losing match into a victory. Players that get stuck on doing the same strat over and over again will lose in the long run, because perceptive players will quickly realize what that strat is, and they will play around it.

Have multiple ways of executing a plan, a couple of favorite operators, and switch them around when you feel you need the edge.

Most people are complacent; they play the game on auto-pilot, expecting stuff to just work. If you throw a wrench into their gameplan, they will not know what to do.

Tangible examples:

• Choose a defense site that normally doesn’t get played. Switch the order of the normal pick meta.
• Play Frost/Kapkan once in the middle of the match to keep the enemy on their toes until the end of the match.
• Attack from different angles. Test their defense by pre-firing, lure defenders to one side, then quickly rotate to hit them in their weaker side.
• Do not be afraid to pre-fire “stupid” walls if you can afford the noise and bullets; I cannot count the time I’ve been killed or got a kill by pure luck.
• Do not run all the time. Siege relies heavily on sound; try walking when you rotate closer to the objective to mask your entry.
• Don’t peek the same angle twice. Always move a bit or change stances if you engage the enemy.

The most important tip is to get into the mindset of playing the game for the first time.
Imagining this is your first time playing frees you from automatic responses. Treating the game as a life-or-death situation helps your natural instincts to kick in, and in a high-paced game, your instincts have much faster decision-making power then your thinking mind.

Please try to keep the surprises ready, be unconventional, and don’t listen to what guides on YouTube tell you; only you know how to play YOUR playstyle the best.

Peace ☮