Yeah, totally agree with the zoom suggestion. Changing lenses in a crowded spot like Shibuya is just asking for trouble, honestly. Since you have the X-T5, you really have to be careful with your choice. That 40MP sensor is super high-res, so it tends to show every little flaw in cheaper glass. You want something sharp enough to actually use those megapixels. A few things to consider for reliability:

• Make sure the lens has weather sealing (WR). Tokyo gets random downpours and you dont want to be stressing about your gear.
• Stick to a lens with internal stabilization or a fast aperture for those neon night shots. I would suggest either the Fujifilm XF 16-80mm f/4 R OIS WR for its versatility or the Tamron 17-70mm f/2.8 Di III-A VC RXD if you want that extra low-light performance. Both fit your budget and stay on the camera all day.

Building on the earlier suggestion, i really think you should look at the weather sealing and stabilization specs above everything else. Tokyo weather is unpredictable, and i've learned the hard way that a dry day can turn into a downpour in minutes. Over the years, i've tried dozens of combos, but for the X-T5, you need something that wont waste that 40MP sensor. I highly recommend the Fujifilm XF 16-80mm f/4 R OIS WR. It fits right in your budget at about $800. The 6.0 stops of OIS are insane for shooting handheld in the Shinjuku alleys at night. It has 16 elements in 12 groups, including three aspherical elements that really help with the clarity on that high-res sensor. Its basically the perfect one and done lens because of the constant f/4 aperture and the weather sealing... honestly, just keep it on the body and enjoy the trip without worrying about dust or rain.

I agree with Indica that weather sealing is absolutely vital for Japan, but unfortunately i had a bad experience with that 16-80mm. Taking it on a trip through Hokkaido, the sharpness was just not as good as expected, especially on the X-T5. It felt kinda mushy at the edges which is a real shame when you've got those 40 megapixels to work with. If you want something that stays on the camera and actually feels reliable, look for a used Fujifilm XF 16-55mm f/2.8 R LM WR. It's a brick, sure, but it's the only zoom i've used that doesnt feel like a compromise. My copy has been out in some pretty nasty downpours and it's never missed a beat. Most of those all-in-one lenses are basically just asking for disappointment once you see the files on a big screen... stick with the red badge stuff if you can find a deal.

TL;DR: The dream of a single perfect travel lens for under 900 bucks is basically a scam these days because quality is dropping while prices keep climbing. Honestly its ridiculous how much these companies expect us to pay for gear that feels like a total toy. I bought a high-end body recently and the frustration of trying to find glass that actually matches the sensor resolution without breaking the bank is just... exhausting. I went on a big trip last spring and thought I was totally set with my one-lens setup, but halfway through, the electronics just started glitching out in the humidity. It ruined my whole mood for the rest of the week because I was constantly worrying about my gear instead of enjoying the scenery. It drives me crazy that $900 is considered a mid-range price point now. Back in the day, that would buy you a pro-grade tank that lasted a decade. Now? Youre lucky if the zoom ring doesnt start sticking after six months. I really feel your pain with the confusion because the marketing makes it sound like every lens is perfect, but once you get it in your hands, the reality is usually pretty disappointing. Its such a struggle to find something reliable that doesnt cost a literal fortune, and honestly, the way the market is going just makes me want to leave the camera at home half the time. Everything is just so fragile and overpriced and it feels like they just dont build things to last anymore.

Robinluce is spot on about the 16-80mm being a bit mushy... that 40MP sensor is no joke and really shows when the glass isnt up to par. Had a moment to think about this and you should seriously look at the Tamron 17-70mm f/2.8 Di III-A VC RXD for Fujifilm X instead! Its seriously amazing and fits right in your budget. Compared to the expensive Fuji red badge zooms, this thing is such a better value for a beginner. The constant f/2.8 aperture is fantastic for all those Tokyo night shots and neon lights because it lets in so much more light than the f/4 options. Plus the vibration compensation is super reliable. I love it because it stays sharp across the whole range which is exactly what you need for the X-T5. Honestly it makes the whole experience way less stressful when you dont have to worry about switching lenses in a crowded city! Youre gonna get incredible shots with this setup.

Can confirm