It looks the Passport's screen was about 3.5" wide. Not many phones have that wide a screen, and of course, it'd be quite tall, with the usual screen ratio. The ZenFone 3 Ultra is pretty close: https://www.asus.com/Phone/ZenFone-3-Ultra-ZU680KL/Tech-Specs/
Yeah, it's a pretty mammoth screen -- 6.8" diagonally. I saw it last year when I visited Taipei, and it was pretty unwieldy. The screen is only FHD (1920x1080), so you can't take advantage of the large screen to look at things in QHD (2560x1440) or 4K.
What's the eye strain from -- the screen quality or the font size?