HMRC vigorously pursue those who promote or enable tax avoidance schemes.
HMRC recently published on GOV.UK a summary of the evidence they provided to Sir Amyas Morse’s Independent Review of the Loan Charge. This includes information on the measures introduced and action taken to tackle promoters and enablers of disguised remuneration and other tax avoidance schemes: https://www.gov.uk/government/publications/independent-loan-charge-review-summary-of-evidence/section-8-powers-to-tackle-tax-avoidance
In addition, HMRC published a policy paper in March 2020 laying out their approach to tackling promoters of mass-marketed tax avoidance schemes, and those who facilitate the use of these schemes. This can be found at the link below: https://www.gov.uk/government/publications/tackling-promoters-of-mass-marketed-tax-avoidance-schemes/tackling-promoters-of-mass-marketed-tax-avoidance-schemes
The Government also announced at Budget 2020 two calls for evidence to assist with future initiatives; a forthcoming call for evidence on tackling future use of disguised remuneration, and a call for evidence on raising standards in the tax advice market: https://www.gov.uk/government/consultations/call-for-evidence-raising-standards-in-the-tax-advice-market.