That is excessive shriveling. Older pbulbs will wrinkle, and lose some plumpness as they age and new growth starts, but what you have is from either underwatering or overwatering. Check the roots. Most Oncidiums do not want to dry completely inbetween waterings, tho I have had some that did like to dry a bit. Use a bamboo skewer in the media to help judge how often to water. The extremely shriveled pbulbs won't likely re-plump after the problem is corrected, but new growth should be good. May take some time for plant to recover, as I suspect roots are in poor shape, either dehydrated or rotted.
Let us know what you find! Good luck!
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