You do not have to celebrate the Resurrection of the Messiah, Jesus Christ, Second Person of the Blessed Trinity.
But claiming such a celebration is not Scriptural is absurd.
The early church didn’t celebrate the resurrection; they celebrated Passover, First fruits, and Pentecost as a continuous event. All of the epistles have evidence of this. It wasn’t until 300 years later that Sunday worship began.
The appointed days have important meaning; they are prophetic; all of them. Sunday is nothing. But Paul also stated not to criticize anyone regarding the keeping of the days; IOW, in Christ there is liberty.