Modern pop's just as great or shite as it's always been. There's fallow periods and better years than others but everything is basically the same over broader stretches of time. What gets exposure is changing, and is more exclusive these days, but the quality of the top 10 this week is roughly the same as it was in any random week in the 70s or 80s. You can't tell me 1976, the year of Save Your Kisses for Me, Combine Harvester, Mississippi, and No Charge, was any better than what's been in the charts in recent years.
Aesthetics and tastes develop and move with the times but "quality" never really goes up or down.
Except for the 2010s, which three of those songs are from. The 2010s are different, they're a cultural black hole. Things are so, so much better now in the 2020s than they were about 10 years ago. The 2010s were a genuinely critical time for mainstream pop where we nearly lost it all. Spotify and Instagram were the dominant forces and literally everyone was happily subservient to them. I've never known a period of pop be so homogenous, so willingly unimaginative, so conservative, so plain.
So thank god for TikTok, which has caused a genuine shift in the music industry and forced a lot of labels back to the drawing board. It's brought through different kinds of artists really unexpectedly and boosted their sales, it's given exposure to classic hits that deserved more time in the sun (Running Up that Hill, Murder on the Dancefloor), and it's forced leading popstars back into being album artists who put together proper projects and own the rights to their tunes. The landscape of current pop is so much more exciting these days - more forward-looking, more diverse, more urgent and demanding of your attention.