It is a stretch to compare long-term gawking of a corpse to a brief funeral layout.
Or the gawking at human remains.
In fact, when a body is too badly damaged the casket is closed out of respect.
Burials are mentioned in the Bible as early as Genesis 23.
I was not equating these rituals point for point, but illustrating that a practice may be reverent and in harmony with Christian faith and morals, without being mandated explicitly by Scripture.
None of our modern funerary customs are mandated in Scripture; I don't think my conclusion can be coherently denied.
To make an even more general point, I would say our culture needs to recover a regard for the body as a temple of the Holy Spirit which will someday glorify Jesus Christ in the resurrection. The Catholic Church does not use motal remains as a sick display, but rather as a memento mori and a call to prayer.
An example would be the 16th-century Chapel of Bones in Portugal, created to encourage Christians to contemplate the transitory nature of life and think soberly of the Final Judgment and future life to come. A sign over the entrance reads, "Our bones that are here await yours."