Having read hundreds of search warrants over 30 years, it is commonplace that agents and cops are less than fully candid in search warrant/FISA applications -- generally by failing to include any and all exculpatory information in the warrant.
It does not mean the underlying investigation is without merit. It does not mean that the warrant/application, in totality, does not pass constitutional/statutory muster. It does not mean that the evidence should be suppressed -- which only happens if the cops/agents intentionally lied or recklessly disregarded the truth --- to the point where no reasonable judge/magistrate would have approved the warrant/application had the truthful information been included.
Google state and federal court appeals dealing with "Franks motions." See how difficult it is to overturn convictions based upon search warrant defects.
For the record, I do not defend any dishonest actions by Government officials who serve the public trust, including most notably the Attorney General and the President.
The FBI decision to run down the information/intelligence re Trump's ties to Russia was 100% righteous. Horowitz confirmed that.