When a critique has no intellectual basis I consider it an attack.
The O&G money is a good example. In order to make a valid comparison to other politicians one must consider the donations as a percentage of their total while factoring in the percentage of GDP that O&G has in their state or district. It is also important to distinguish small individual donations from PACs. Given the percentage of Beto's total donations and the percentage of state GDP, Beto did not receive very much from the O&G sector and it was individual contributions.
The M4A thing is similarly irrational. Progressives claim that if you don't support M4A a person is not a progressive when M4A is only a label and has nothing really to do with a realistic implementation such as Bernie's 2017 bill. Realizing that, Beto refers to the more generalized term universal healthcare. The progressives then say he is wisshy-washy or not progressive and a centrist, and can probably be manipulated by big healthcare to stop M4A. Then the centrist and rightist Dems and big healthcare are thinking Beto and Biden are both going to stop M4A, so they are good candidates for them. None of us know how hard Beto would push for M4A if elected or if he would cave to corporate interests.
The kill ICE thing is another. Beto did not line up behind killing ICE because he recognizes that there are a number of ways to restructure the immigration system, so progressives say he is not progressive enough. This is a stupid attack, not a rational critique.