Nope, haven't gotten bored yet. Perhaps you're just doing it wrong? In my experience, the ones getting bored are the ones who think they have to play Minecraft in a certain way and they never even try to play it any other way. Worlds don't last forever (whether you want them to or not), so it can be pretty boring pretty quickly just doing the same things over and over in the same order.
I get bored but I find things to do still to keep with the game, I should take breaks but I find more to do. Like survivals don't jump out at me anymore (1.2.5 I played with mods, 1.7.10 to 1.12.2 with mods and I just play it less and less not just due to familiarity of mods mainstream or niche but just playing the game's mechanics over and over or not jumping to more biomes, new mechanics or just simple things, but I have had an oversaturation of the games so that doesn't help of course mostly since the experiences are great of course),
But these days I make modpacks, puzzle maps or document/test out 1.13.2 Rift or 1.14 Snapshot Fabric mods to keep with the game more so than play it. I know not all can relate to that but it's why I still stick with the game since I don't really play it that much. I have gone to the niche side of modding, I've played snapshots sometimes more so with Fabric mods technically so I can count that when I notice things in them besides just testing them/playing a bit in them normally. But Vanilla 1.13 I played briefly but not too long and past versions are fun but mods are my motivation for a lot of things these days to stick with the game. The base game is great, I just have few ideas for building, exploration experiences and other factors.
I hope that this is a good enough some up and is understandable for those that don't use mods or have no clue what I'm talking about with alternative modloader like Rift & Fabric being the driving forces for me sticking with the game these days.
My signature is a good example of what I do of course.
The Meaning of Life, the Universe, and Everything.
I'll add that when the devs change the mechanics of the game its painful at first but it helps keep you on your toes and making it interesting. Like the upcoming villager mechanics for 1.14. I've pretty much mastered the village thing and created my own underground Iron Farm design. But changing the way what makes a house broke the farms, but the more I learn about the new mechanics the more it makes sense. Also the villager leveling makes more sense and is more useful. The breeding and Iron golem spawning is now voted on in the town center. Its soooo cool, I can't wait for 1.14. In the mean time Im playing the snapshots. I rarely have EVER played a game where new development actually improved the game play. Usually things get dumbed down.
Oh yeah also if you want a challenge the pillagers are brutal, try defending the villages and help out with defense, fun stuff. This will be the most interesting update since the Redstone update IMO.
I've only played Minecraft since 2017, but I can't imagine getting bored with it.
I installed Fortnite today just to see what all the hype is about, and it is a mystery to me why players bring it up as if Fortnite were the logical alternative to Minecraft. For me, they are so dissimilar that it's like saying "Playing baseball is getting boring so I've decided to take up swimming".
I only played Fortnite in Creative mode for about half an hour, but that was enough for me. I won't be loading it again.
Minecraft is a game. It's something to be enjoyed. Try mods or challenges. Try taking a break and playing some other games, and come back when you feel ready. You might not want to come back at all, which is fine, as long as look back on good memories :).
I've been playing for 6 years and pretty much the same way on basically the same version and have yet to get bored, even as many others wonder why I find caving to be so fun. I do play on modded worlds from time to time but even those are just more of the same thing; my current world is a recreation of one of my earliest worlds, and my first modded world, which simply doubled cave generation; the current world was more intended to be something to play on while working on a major update to TMCW but I've more recently been playing on it more than updating and have spent far more time on the recreation than on the original world, making it one of my largest and longest-played worlds (either way, I have no set goals on when TMCWv5 will be finished as it is just a fun side project; the time I spend on making mods is in itself considered to be the same as actually playing):