It may be best to presume that instead of blocking 'beneficial' things that the Government might do - that McConnell is instead adhering to an anti-liberal agenda that he thinks is best for the country overall. It's a cheap shot to presume that those who disagree with you are acting in bad faith out of some inherent evil nature.
McConnell is one of the most skilled politicans in Washington and the democrats would do well to try and limit his influence - that's easier said than done in a 50/50 split and he can still cause no end of trouble and delay. I suspect Shumer thinks it's better to have McConnell in the boat pissing out than on the outside pissing in. With the extreme right of the Republican party in the naughty corner, it might be a good time for both parties to consolidate the centre ground voters. McConnell is a pragmatist, it may not be in Republican interests to continue the sulky toddler approach of the Obama era and the maverick badass schtick of the Trump tenure.
Time will tell - and you've got to give Schumer a chance to try negotiation first. That's likely to be the Biden way. It's hardly like the Dems have got a resounding mandate from the people - the country is fairly evenly split. Time for some actual maturity at the top.