Trump himself connected the July 25th phone call on Biden to Ukraine's funding...
"... After days of insisting there was nothing inappropriate about his telephone call with Zelensky, President Trump, in two sets of remarks to reporters asking about his July 25 phone call with Zelensky, appears to confirm a connection between U.S. financial assistance for Ukraine and his pressure for the country's leaders to pursue the investigation he wants.
On Sept. 22, Trump acknowledges discussing Joe Biden with the Ukraine leader during their July 25 phone call. "The conversation I had was largely congratulatory, with largely corruption, all of the corruption taking place and largely the fact that we don't want our people like Vice President Biden and his son creating to the corruption already in Ukraine," Mr. Trump told reporters. Trump says, "Certainly I'd have every right to raise Biden with Ukraine President if there's corruption and we are paying lots of money to a country."
Trump has repeatedly referred to what he falsely claims the Bidens to have done as "corruption." "It's very important to talk about corruption," Trump tells reporters on Sept. 23. "If you don't talk about corruption, why would you give money to a country that you think is corrupt? It's very important that on occasion you speak to somebody about corruption."..."
The very next day on September 24, Pelosi announced an impeachment inquiry into Trump's quid pro quo with Ukraine...and three House committees opened investigations.
All the testimony that you call opinions are consistent with Trump's own statements.