'...You have subjected all things under His feet.' For in subjecting all things to Him, He left nothing unsubject to Him. But now we do not yet see all things subjected to Him. Heb 2:8. For You have caused Him to rule over the works of Your hands; You have put all things under His feet. Psa 8:6.
What's not yet seen is the next age: the 1000-year direct physical rule of Christ with His overcomers, on (the old) earth, over the sheep of Mt 25:31-46. Rv 2:26-27; 12:5, 11; 20:1-7.
For it was not to angels that He subjected the coming inhabited earth, concerning which we speak. Heb 2:5.
And when He brings again the Firstborn into the inhabited earth, He says, 'And let all the angels of God worship Him.' 1:6. 'Sit at My right hand until I set Your enemies as a footstool for Your feet'? 1:13.
For if Joshua had brought them into rest, He would not have spoken concerning another day after these things. So then there remains a Sabbath rest for the people of God. 4:8-9.
Christ also, having been offered once to bear the sins of many, will appear a second time to those who eagerly await Him, apart from sin, unto salvation. 9:28.
This One, having offered one sacrifice for sins, sat down forever on the right hand of God, henceforth waiting until His enemies are made the footstool for His feet. 10:12-13. Exhorting one another; and so much the more as you see the day drawing near. 10:25. [G]reat reward. For you have need of endurance in order that, having done the will of God, you may obtain the promise. 'For in yet a very little while the Coming One will come and will not delay.' 10:35-37.