Regarding Uzzah and the LORD, God does not need man's help.
Uzzah's action did not treat God as holy. The ark was no idol, it held the presence of God in their midst. God always reaches out to a man first on God's initiative, not man aiding the LORD who needs no help.
The LORD was also angry with Moses when Moses struck the rock at the waters of Meribah. Moses was to speak to the rock, but Moses struck the rock in wrath calling Israel rebels.
Numbers 20
7 Then the Lord spoke to Moses, saying, 8 “Take the rod; you and your brother Aaron gather the congregation together. Speak to the rock before their eyes, and it will yield its water; thus you shall bring water for them out of the rock, and give drink to the congregation and their animals.” 9 So Moses took the rod from before the Lord as He commanded him.
10 And Moses and Aaron gathered the assembly together before the rock; and he said to them, “Hear now, you rebels! Must we bring water for you out of this rock?” 11 Then Moses lifted his hand and struck the rock twice with his rod; and water came out abundantly, and the congregation and their animals drank.
12 Then the Lord spoke to Moses and Aaron, “Because you did not believe Me, to hallow Me in the eyes of the children of Israel, therefore you shall not bring this assembly into the land which I have given them.”
13 This was the water of Meribah,[a] because the children of Israel contended with the Lord, and He was hallowed among them.
When you do not obey the voice of the LORD, to follow His commandments, they you are not treating Him as holy. The LORD was in covenant relationship with Israel, and so Israel was expected to follow the commands and ordinances of the LORD, but not so the gentile nations. When the ark was taken, they likely touched it without being killed not because they knew the LORD, but because they did not know the LORD. God also had a purpose to weaken the Philistines and show them their gods were powerless, that He was the true God of all the earth. Those gentile nations thought each god had power over only certain areas, as local gods. God determines in each case, Moses, Uzzah, Nadab, Abihu, the Philistines, the appropriate judgement.
Leviticus 10 New King James Version (NKJV)
The Profane Fire of Nadab and Abihu
10 Then Nadab and Abihu, the sons of Aaron, each took his censer and put fire in it, put incense on it, and offered profane fire before the Lord, which He had not commanded them. 2 So fire went out from the Lord and devoured them, and they died before the Lord. 3 And Moses said to Aaron, “This is what the Lord spoke, saying:
‘By those who come near Me
I must be regarded as holy;
And before all the people
I must be glorified.’”
So Aaron held his peace.
Nadab and Abihu also did not treat the LORD as holy by what they did offering strange fire, something which the LORD had not commanded them to do. Those who come or draw near to God must do so treating Him as holy, meaning to be obedient to what He tells them. Do not come before the LORD and give Him your gifts on the altar, if you are at odds with your brother, as in you have sinned against your brother. First make it right with your brother, and then come back to the LORD to offer your sacrifices, which includes praise and worship today.
In a similar manner today, some despised, did not treat as holy what our Lord Jesus Christ did and ate unworthily the bread and the wine of the Lord's last supper and many were sickened and many died. So not just a few had this happen to them.
1 Corinthians 11:30 For this reason many are weak and sick among you, and many sleep.
So true then today, there are judgements on us from the LORD if we do not treat Him as holy. But there is greater judgement on those who do know better. Just like it says about those who teach the word in James.