Why does God limit the damage Satan can do? Are Satan's actions bad?
Please note that in the book of Job, that is exactly what God does....
Job 1:8 And the LORD said unto Satan, Hast thou considered my servant Job, that there is none like him in the earth, a perfect and an upright man, one that feareth God, and escheweth evil?
Job 1:9 Then Satan answered the LORD, and said, Doth Job fear God for nought? Job 1:10 Hast not thou made an hedge about him, and about his house, and about all that he hath on every side? thou hast blessed the work of his hands, and his substance is increased in the land. Job 1:11 But put forth thine hand now, and touch all that he hath, and he will curse thee to thy face.
Job 1:12 And the LORD said unto Satan, Behold, all that he hath is in thy power; only upon himself put not forth thine hand. So Satan went forth from the presence of the LORD.
The action is bad, but can be employed to work good in beings' spirits -then all that was destroyed can be renewed. It is the ruin or health of a being's spirit that is most important to focus on -the ruin or health of the environment is secondary -and is a result of the former.
Also, Christ overcame sin, and Satan's temptation. To say Christ overcame Satan might give the wrong impression. Satan and the demons had long since been restrained -doing only as God allows. Satan had attempted a coup (probably from earth, as he said to himself "I will ascend above the heights of the clouds, I will be like the most high") along with the demons he turned even before he was present in Eden. It was put down, and they were restrained. It is not ours to say that there is no hope for Satan -but neither is it wise to consider him too much, as it is specified that he does not have our best interest at heart at this time. It is written that even angels do not accuse or judge him, but say "The Lord rebuke thee".... (Jude 1:9).
It is written that the demons await judgment -and that while God's longsuffering still waited, the being which became Christ went by the spirit and preached to them (I Peter 3 18-20) Some believe verse refers to spirits of men in purgatory -it does not -it refers to ...
Jud 1:6 And the angels which kept not their first estate, but left their own habitation, he hath reserved in everlasting chains under darkness unto the judgment of the great day. It is specified that Satan will eventrually be cast into the lake of fire -but it is not specified how God will eventually judge all the demons. All men who have ever lived, and who are not resurrected to the first resurrection at Christ's return, will be resurrected to the "judgment", and be judged according to their works. Though some may never have heard of God -if they did good works -and did not do evil works, they will fare well.