Is the view of God being angry in the Old Testament from God setting opportunities for souls to be compatible with the Kingdom?
Did the "anger" stop because Jesus started a new way out of this fallen condition?
What makes you think the anger stopped? God doesn't change.
In the Old Covenant, because He knew we were weak because of the carnal nature, He provided laws that a weak person could keep. Romans 8. They were basically the bottom line, but nothing a weak person couldn't accomplish in his flesh, though could not bring them up to actually being righteous. But God is holy, so had to overlook the shortcomings previously committed under the law before Christ came. Romans 3. He also accepted the covering of sin by the blood of bulls and goats. What I think made God angry, is His people didn't even try to keep the shallow laws they could have easily kept.
The New Covenant is completely different. The laws of God are not shallow. Instead they actually make a person holy. But certainly the carnal nature could not keep these, so Jesus sent His Spirit to indwell us and supernaturally separate the carnal nature from the newly created nature that partakes of Christ's divine nature. If we continue to walk in the Spirit, we are able to never fulfill the lusts of the old flesh, but instead fulfill the completely righteous requirements of God's eternal laws. We do not have to do anything of ourselves; Christ does it all through us. We just need to rest in His leading. IOW, we just do nothing against our now super-sensitized conscience where the Spirit dwells.
So if you thought God was angry in the Old Testament, He is doubly angry in the New Covenant, where everything we need to be righteous is provided freely by Him. Hebrews 10:26-31 below. To receive His Spirit we just have to acknowledge our sinful nature is weak and repent of that weakness and want to be righteous. Be honest with God. If you want to still sin, and just want a ticket to heaven, God will ignore you and you will not receive the Spirit, until you actually repent for the right reasons. I know! I didn't receive the Spirit for 30 years!
26 For if we sin willfully after we have received the knowledge of the truth, there no longer remains a sacrifice for sins, 27 but a certain fearful expectation of judgment, and fiery indignation which will devour the adversaries. 28 Anyone who has rejected Moses’ law dies without mercy on
the testimony of two or three witnesses. 29 Of how much worse punishment, do you suppose, will he be thought worthy who has trampled the Son of God underfoot, counted the blood of the covenant by which he was sanctified a common thing, and insulted the Spirit of grace? 30 For we know Him who said, “Vengeance is Mine, I will repay,” says the Lord. And again, “The Lord will judge His people.” 31 It is a fearful thing to fall into the hands of the living God.