要确保$sentTo在两个条件都为false时是空集合...

$admins = collect(new User);
$owner = collect(new User);

if (config('personal.mailing_technician')) {
    $owner = $event->ticket->ownedBy;
}

if (config('personal.mailing_admin')) {
    $admins = User::query()->role('admin')->get();
}

$sentTo = collect(); // Initialize an empty collection

if ($admins->isNotEmpty() || $owner->isNotEmpty()) {
    $sentTo = $admins->push($owner);
}

if ($sentTo->isNotEmpty()) {
    // Do something
}