Are UK Government strict towards researcher whose sole purpose of visit is for tourism?
Under ‘Business - General Activities’, gathering information for a visitor’s employment overseas is a permitted activity (see App3, 5A https://www.gov.uk/guidance/immigration-rules/immigration-rules-appendix-v-visitor-rules)
If you are going to the UK only for tourism, and not intending to do anything work-related in the UK, then it does not matter what your job is.
The job you have might affect your chances of getting a visa. If your job is much higher paid in the UK than in your country there might be a suspicion that you were trying to relocate illegally to the UK. If your job is low-level, or temporary, or easy to transition out of, then it is not considered as much of a tie to your home country as a well-paid long-term in-demand job. If your job is one where a visit to the UK would often be a part of your work, you might have to provide extra evidence to show that you will not be working.
The job title of 'researcher' is far too vague for us to comment upon whether that applies to you.