Unfortunately, the quality needed to play test cricket in different conditions is very quickly diminishing. The money now available playing the shorter format of the game trumps test cricket. I have sympathy for the players. They go with a different mentality and are coached differently whilst with franchises and then again differently with their national teams for test cricket. Difficult to make alterations between these formats in such a short time. You can probably name just 2 batsmen in any national team who you would say are still capable of playing test cricket at a high level.
Is it any wonder there are now voices trying to promote 4-day tests simply due to the quality of players in this format?
Bit of both I guess. Pitches are definitely curated to favour the bowlers. I think I remember Virat or someone saying something along the lines of "we'll see England in India" after the thrashing they gave us in 2011 and since then it feels as if test cricket has taken a different route (predominantly in the sub-continent). New Zealand are a better team than they ever were (?) which makes touring them incredibly difficult. Australia is always flat but still challenging. SA and England are tailored towards the fast bowlers. India and Sri Lanka (maybe even Pakistan) have completely change the nature of their pitches from flat to spinning from day 1. It's a little ironic given the complaints from the previous era about both being flat track bullies.
That and the fact that we've an abundance of brilliant bowlers - Broad, Anderson (is it a coincidence that they're at their best during the past few years - favourable conditions is a definite factor however small), Starc, Cummins, Hazelwood, Boult, Southee, Wagner, Jamieson, Rabada, Ngidi, Ishant, Shami, Ashwin, Jadeja, Bumrah, Kemar Roach has been brilliant for WI and maybe Abbas for Pakistan and Herath for Sri Lanka - to name a few. Batting is definitely not as easy as it used to be. How many batsmen average 50 in this era? Root, Kohli, Smith and Williamson aside, I can't think of another. Marnus is still very early in his career.
This whole pitch this, pitch that literally only ever comes up in India - Perth is allowed to have a million, trillion cracks and Trent Bridge and Jo'Burg are pretty much played on grass. There is a definite case of "learn how to play against spin" - it's a facet of the game and for some odd reason, England refuse to want to get better.
India took a risky approach in curating such a wicket but it gave England are fair chance to win unlike in 2016, for example, where the wickets didn't induce as much spin and we whitewashed them. Which is better?
Cricket has shifted, for now, but maybe it'll change again? What will never happen, unless the ICC chime in, is pitches in India changing. Unfortunately, it's a matter of get good or get out - It'll be the same when we tour England (where we'll most likely get thrashed).