I've been using the same battery for 4 years in Sharjah am I driving a time bomb?

I think I might have a record or something and I'm not sure if I should be proud or terrified. I have a 2013 Toyota Land Cruiser and the battery that's in it right now was installed 4 years and 3 months ago. Yes, you read that correctly. Over four years. And the crazy thing is that the car still starts perfectly every single time. No slow cranking, no dim lights, no warning signs at all. I park in shaded parking at home and at work, so the battery never sits in direct sun. I also drive about 45 minutes each way to work, so the alternator has plenty of time to fully charge the battery every day. And I check my battery terminals every month and clean off any corrosion immediately. I found https://uaeedge.com/how-often-car-needs-new-battery-sharjah-2 and the article says most batteries in the UAE last 2 to 3 years maximum. So am I just lucky, or is my battery a miracle? Or am I driving around on a battery that could explode or fail catastrophically at any moment? I've heard that very old batteries can develop internal shorts or even catch fire. Is that true? Should I replace this battery immediately even though it seems fine, or should I keep using it until it shows signs of weakness? I'm worried that because it's so old, it might fail suddenly without any warning, leaving me stranded. But I also don't want to replace a perfectly good battery that might have another year of life left. Is there a way to test the internal health of a battery to know if it's still safe? I've heard of load testers and conductance testers – would those tell me if the battery is at risk of sudden failure? I'm not a mechanic so I don't know what to trust. Has anyone else gotten 4 years or more out of a battery in Sharjah? What did you do to make it last so long, and did it eventually fail suddenly or did it give you warning signs? I'd love to hear from other people with long lasting batteries. Please share your experiences because I'm trying to decide if I should replace my battery now or keep riding my luck. Any advice from battery experts would be really appreciated. I just want to be safe without wasting money.