I used Ditto often during Generation 8, namely in Pokémon Sword. Ditto was a great Pokémon, being one of the very few Pokémon that could counter Zacian, the most broken Pokémon at the time. Ditto has potential to be one of the best revenge killers ever. For instance, when you send out Ditto with the Ability Impostor against Zacian, it transforms into it, copying its base stats (except HP I believe), Ability, and stat changes. Using a Choice Scarf, it is guaranteed to outspeed anything it transforms into (assuming it doesn't have a Choice Scarf of its own), and can one-shot Zacian with a single Behemoth Blade. Ditto is also great for transforming into Pokémon with weaknesses against their own types such as Dragon and Ghost, as well as Pokémon that boosted their stats a lot, which is great for reverse sweeping. As a result, I used Ditto a lot. Nowadays, even though Ditto is still good, it can be countered by the Tera Type mechanic. For instance, if someone plans on sweeping my team with a stat boosted Miraidon, I could bring out my Ditto to transform into Miraidon and KO it with its own Draco Meteor, but my opponent can easily counter this play with a Fairy Tera Type. As a result, I don't often use Ditto this generation for battles, but I still do use my Ditto for breeding.