Boredom is good. Being bored is great in many ways.
By far the most important part of boredom is the repetition. Only with repetition do we get better. I love seeing the max reps I can do climb ever higher. Until I hit a plateau, doing the same movements, the same programs week after week is the best way to progress.
What gets measured gets improved. That's my favorite version of the often overused mantra. THere's no way I can improve if I don't know where I stand compared to the last time. Doing "random" workouts each week is like comparing pounds to stone to kilograms.
Knowing I'm progressing is the biggest motivator that keeps me consistent.
Sometimes progress isn't enough to keep my brain from wanting more. The same boring workouts are great for my progressing elsewhere too.
The brain works on problems, in the subconscious mind when the conscious mind is relaxed. Everyone who has banged their head against a problem for half an hour then solved when they stopped trying knows this works. Boredom allows the mind to wander, to wonder, to let go of what was so difficult. The letting go is key.
Focus On The Minutiae
Instead of letting my mind wander, many workouts benefit from focus and attention. Anybody who has tried olympic weightlifting knows this.
One way this works really well is by focusing on the muscles that are doing the work, I create a stronger mind muscle connection, which has been shown to create more progress.
Another way is improving form of a movement. Sometimes I catch myself going through the motions of an exercise I've done countless times, only to later realize that I'm not improving because my form or technique sucks.
I make what I do better by not clouding it with "new stuff".