Aside from the brazen lying and their own co-conspirator status, one of the reasons the Trump defense team's rhetoric has seemed to fall flat during today's Senate impeachment opening moves, is that they seem to have been prewritten with little care for what House impeachment managers would actually be arguing. House managers are treating the debate on these opening amendments, which would force the Trump administration to produce documents and testimony to the Senate that they have refused to provide to the House, as their true "opening statements." Trump's legal team, however, is treating them as perfunctory.
One of the clearly pre-written claims from Trump's allies is that the request for documents and testimony from Bolton, Mulvaney, and other key White House officials shows the House "isn't ready" to present their case. Lead manager Rep. Adam Schiff spent a bit of rebuttal time blasting that claim into low orbit.
Schiff has been subtly and not-so-subtly hammering his Senate listeners on this very point: Impeachment managers have a case to make, and if the Senate chooses to block that case on behalf of Trump and their own party then that is on their heads, and on their records. The public will know. We know what documents and witnesses are being requested, but are being withheld by Trump's allies: The Schumer amendments described them in detail. Two thirds of American voters believe the Senate should call those witnesses and obtain those documents.
If Senate Republicans block those efforts nonetheless, that will not make the evidence disappear. It merely delays the day when each bit of evidence does come out. And it makes it crystal clear that Senate Republicans were not just dismissive of that evidence, but acted as co-conspirators in Trump's attempts to hide it.