Impeachment is only an accusation. Unless investigated and proven there is sufficient evidence of high crimes and misdemeanors to lead to formal charges and a conviction, he is not disqualified to hold office.
I suspect Pelosi is hoping this time there will be sufficient Senate support for charges and a conviction to disqualify in 2024.
They are afraid of Trump and his support base so they will attempt anything they can to emasculate him and destroy his support base.
Seems odd there were plans posted on social media in advance of Jan 6 about a siege on the Capital, yet neither FBI nor US defense reported that to the President, Congress or Capital Police.
Also odd that the Capital had so few Police on-duty on the day there was to be a joint session to review highly controversial election results on the same day as a large rally which was likely to protest outside the Capital building.
Apparently, those that broke-in did not attend the Trump rally but were already doing so before the rally was completed and before the crowd departed for the Capital.
I have heard there has been photos showing Capital Police holding doors open for invaders to enter and I've seen photos showing Capital Police posing for selfies with some of those that entered. It seems many who entered, may have thought they were on a tour which is why they were calm and remained within the roped areas.