I think a “normal” inverted T consists of half-height keys (i.e. used on most current laptops). ThinkPads used slightly higher arrow keys for a while, not sure about now.

A normal inverted T is what is on a standard desktop PC keyboard: https://upload.wikimedia.org/wikipedia/commons/8/8c/Arrow_ke...

While half-height arrow keys have become common on laptops, that's probably not what GP (https://news.ycombinator.com/item?id=44769440) meant by "normal".

ThinkPads generally use slightly smaller keys for the arrow keys, but still significantly taller than half-height, like for example here: https://p3-ofp.static.pub/ShareResource/560x450/SSNP/4Y40X49...

What people really want is a full-height inverted T like on this Lenovo gaming laptop: https://p1-ofp.static.pub//fes/cms/2025/05/21/uft1eixrszoryp...