The impeachment trial is a political proceeding and not a judicial proceeding. Rules on inhibition that apply to our court system do not apply to a political trial. There are as many senators who have been critical of the Corona court decisions as there have been defenders. If the rules of inhibition are strictly adhered to in a political proceeding then all the political positions taken by all the senator judges could be made basis of inhibition and there will be no one left to try the respondent.
Ultimately, in a very public trial like this one where the evidence, the line of questioning as well as the answers given for or against are to be seen and witnessed by the entire nation, it will be the public who will decide whether or not we will be biased and it will be the people who will judge us politicians by denying us their vote in any future election should they feel we were remiss or we failed to exercise discretion in our conduct as senator judges. This in essence helps describe the political nature of an impeachment proceeding.