> they are about the only way to comply except pure BEVs
On paper. In reality [0][1] unless you drive all electric all or most of the time the actual, real life CO2 emissions are far worse. Because now you have an ICE engine that hauls around an extra battery and electric motor, occasionally inefficiently charging the battery by burning gasoline.
Many (most?) PHEVs owners don't have charging at home (reason to buy hybrid), and the rest of the charging infrastructure is far more inconvenient to use than a gas station. Depending on where you live it may also prove more expensive to drive electric. Add to this the small battery and you see why most of them are driven mostly in ICE mode.
This being said, if I were in the market for a new car I really wouldn't care about what the government promises will happen in 2030. I'd look around to see what makes sense for me. Is the government doing anything about it? Are they heavily investing in making this a reality (new chargers, new electrical infrastructure, etc.)? Talk is cheap.
[0] https://theicct.org/publications/phev-real-world-usage-sept2...
[1] https://www.telegraph.co.uk/news/2020/02/05/revealed-plug-in...