There have been 143 offensive tackles at the NFL combine who have measured 79” tall or taller and Mike McGlinchey is one of them. For those who don’t math very well, 79 inches is six foot seven. Some of them, like Trent Brown have extremely long arms. Having really long arms is good for an offensive tackle because it allows you to generate space and separation with your punch in pass protection particularly if you have longer arms than the defender who you are blocking.
On the flipside, having really short arms, usually means you don’t play tackle.