I think general agreement is that cards’ power should either stay somewhat related to their provision cost or go beyond it after carefully planned combo/as an uninterrupted engine. Those 3 cards completely disregard those rules. They don’t need leader, they don’t need any other cards, just one enemy card with a bit of boost and they point slam for 2 or 3 times their provision cost. Even in realistically worst possible scenario of targeting a unit with 4 power and no boosts they pull off 41 points for 24 provision. With 8 power, 7 boost it goes up to 65. Ways of countering them are very limited with Yrden basically gone and points quite evenly spread across 3 units.
They are too strong, too reliable, too resilient to counters and therefore should be nerfed. Particularly Guillaume. He’s the one outing insane point swing into the combo that other 2 cards can play with.
Source: https://www.reddit.com/r/gwent/comments/yzbw41/could_we_actually_properly_address_the_3piece_ng/