Obstruction of justice must establish criminal intent. Good luck with that. The president is doing his job under Article II of the Constitution.
Perhaps you are right in a technical view. However, this is not a single trial of someone.
Mueller and his minions are wrecking the lives of all they can access who are peripheral to President Trump. It makes others fearful, it scares targets into deflecting, it rewards lies to let these targets escape and create charges against the President. Even false charges or silly claims can lead to charges, indictments etc which can lead to impeachment attempts forever non-stop.
The Mueller team will say, let a jury sort it out or let the congress sort it out, “we did out job by ferreting out sworn allegations or conflicts in testimony for a jury to look at. The bigger the mess a special prosecutor makes the more he is loved by the side opposing the target.
Mueller is already differing espionage to other prosecutors — his goal is take-down his target, DOJ scum for life.