Trump's White House fetes for new SCOTUS justices, with partisan invitees, are NOT normal.
Past presidents typically avoided them, in a nod to judiciary branch's independence. Justices' were sworn in at the Court.
The late Justice John Paul Stevens wrote about this:

Stevens:
"The ceremony should take place at the Supreme Ct whenever possible. The 3 branches of our govt are separate & equal. The president & the Senate play critical roles in the nomination & confirmation process. After that... the ‘separate but equal’ regime takes over.”

Two years ago, Trump began the WH celebration for the new Justice Kavanaugh by apologizing “on behalf of our nation” (more than half of which opposed Kavanaugh, polls showed) for the allegations of sexual assault he'd faced-- or “lies and deception,” as Trump put it.

Trump, posing on the White House balcony with new Justice Amy Coney Barrett, is an unprecedented bit of staging. Unprecedented because the 3 branches of government traditionally maintained the appearance of separation of powers, and of the independence of the judiciary.

At the WH festivities for Barrett tonight, as with Kavanaugh on Oct. 8, 2018, the audience is entirely Republican, including senators, Justice Clarence Thomas and his wife Ginni Thomas, a conservative activist, and leaders of conservative organizations.

For Barrett, as for Kavanaugh & Gorsuch, the question of their judicial independence from Trump was/is a legitimate one given his many suggestions they'll rule as he wants. That their 1st act as justices was to agree to a WH fete with a partisan crowd only heightens the concerns.